Over Seventy Scopes!! - Brief Review
by Todd Gross updated 04/09/06
(PHOTO TAKEN WITH 2 OF THE SCOPES BELOW 11/99)
Over the past four decades I have owned, or borrowed nearly 70 telescopes. (Over 7 dozen including doubles) While I have sold almost all of them, I have also owned all except 3 in just the past 7 years! This "mania" has led to this article, a brief look at each scope (some more than others) in an attempt to give the amateur astronomer an idea of some of the strengths and weaknesses of each. Note that I only recently got into astrophotography, so did not address that issue very much in the reviews. Also note that as usual, it is very possible that I may have gotten some of my facts wrong, if I did, my apologies in advance to any manufacturer or user that disagrees with my findings, I am certainly willing to correct it. Also, my opinions have changed since I began writing this to some degree, so you may find quite a few discrepancies. Dates I got the scopes are posted at times below, the early ones are approximate.
Contents: (click on
scope and it will automatically scroll down)
1. Moonscope 3" reflector (1961)
2. Monolux 60mm refractor (1965)
3. Homebuilt 8" f/8 reflector (1971)
4. Celestron C5+ f/10 SCT (1994) & C5 OTA (2000)
6. Meade LX200, 8" f/10 SCT (1995)
8. Celestron Ultima 2000 8" f/10 SCT
9. Takahashi FC-100 f/8 Refractor (2)
10. Astrophysics Traveler 105mm f/6 Refractor (4)
11. 70mm Televue Pronto f/6.8 Portable Refractor (3)
12. 7" Meade Maksutov f/15 Maksutov (1996) (2)
14. Meade 12.5" Starfinder f/4.8 Newtonian Dob Reflector (1996)
15. 16" Starmaster Truss Newtonian Dob reflector, f/4.59 (1997)
16. Meade ETX, 90mm f/15 Maksutov (4), INCLUDING ETX-EC (1997-1999)
17. 80 mm f/6 Vernonscope Brandon Portable refractor
18. Takahashi 60mm FC-60 f/8 refractor (2)
19. Takahashi 78mm FS-78 f/8 refractor
20. 63mm f/5.6 Vernonscope Brandon refractor
21. 100mm LZOS f/10 Maksuto(1997)
22. Televue Ranger 70mm f/6.8 portable refractor
23. Astrophysics f/8.5 120mm Star 12 ED
24. 6" f/12 Intes Maksutov mk-67 (3)
26. Celestron C102 - 4" f/9.8 refractor
27. Palermiti 43mm miniscope (2)
28. 5" Takahashi FS-128 f/8, 5" apo refractor (2) and FC-125 (1)
29. Bausch and Lomb 4000, 4" SCT
30. Meade 6" f/3.6 Schmidt-Newtonian
31. Celestron 5.5" f/3.64 "Comet Catcher" Schmidt-Newtonian
32. Vixen 90mm fluorite f/9 - (3) (1997, 2001)
33. ORION (Telescope/Binocular Center) 80mm Short-tube refractor - f/5 (and CELESTRON Unit)
34. Intes 6" MK-65 Maksutov f/10
35. Palermiti 60mm Mini-refractor
36. Celestron/Vixen 55mm Fluorite (1998)
37. Televue 85mm APO (1998,2000) (2)
38. Universitiy Optics 80mm Portable (1998)
39. Astrophysics 130mm EDF f/6 (1998)
40. Televue 85mm "Bizarro" (1998)
41. 12.5" Portaball from Mag1 instruments (1998)
42. Starmaster 7" Classic (1998)
43. Starmaster - 18" Stabilite with GOTO drive (1998)
44. C9.25" Optical Tube Assembly (1998)
45. Astrophysics 155mm EDF f/7 (1999)
46. Homebrew 6" f/5 portable scope with starsplitter then spooner optics (1999)
47. Lomo-Astel 80mm f/6.3 rich - field (1999)
48. Intes MN-56 5" Mak-Newt (1999)
49. Astrophysics Stowaway 92.5mm f/4.9 apo refractor (1999)
50. 10" "Teleport" Reflector w. Zambuto optics (1999)
51. 8" Portaball from Mag 1 - Special 2" version (1999)
52. NEW 60mm FS-60C, 60mm f/5.9 from Takahashi (1999)
53: 70mm Celestron Fluorite f/8 (1999)
54. Takahashi 225mm SCT f/12 (1999)
55. The Takahashi FSQ106 refractor f/5 (12/99)
56. The Takahashi CN212 convertible scope (3/00)
57. The William Optics 100mm F/8 Fluorostar (3/00)
58. The Takahashi FCT-76 (2000)
59. Meade 10" F/6.3 SCT Optical Tube
60."YANG" 105mm f/6.2 APO Refractor?
63. The Pentax 75mm SDHF (f/6.7) APO
66. DGM 4" OA Newtonian - Handed over to Ed Ting
67. Starmaster 14.5" EL Hybrid (Rec'd 9/2000)
68. Takahashi FCL-90 "Sky 90" 90mm f/5.6
69. Edmund Scientific's 4.5" f/5 Astroscan
70. JMI NGT-6 Split Ring Equatorial
71. Takashashi FCT150 f/7 (4/2001)
72. Orion BT-80 Binocular Telescope!
75. The Televue 76mm 76mm APO, 3/02
CLICK HERE FOR:
SUMMARY OF CONCLUSIONS
1. Moonscope 3" f/6 reflector (~1961,1999) (2) ... As a child I was given a "moonscope" (by Harmonic Reed) as a gift. All I remember is that indeed, the craters of the moon looked great! It was only one magnification. This small, reflector knocked my socks off as a young boy. 1999 update: Received a new (second hand) one in 1998....being sentimental. It is so flimsy by today's standards I haven't even taken it outside yet. Looking at the scope and the instruction booklet intact brings back so many memories. The instructions are excellent, better than the scope itself!.
2. Monolux 60mm refractor .965 eyepieces (~1965) (f/15?)... I sold this scope recently, but didn't take the time to look through it again with better eps, since I didn't have any .965 eyepieces handy. I believe the optics were good except significant color fringing was evident. I think I was able to see the Great Red Spot on Jupiter in the 1960s with this scope, but it was a darker feature then.
3. Homebuilt 8" F/8 reflector (~1970), mounted on a German Equatorial Mount... A great scope, but it got me out of astronomy because it was so hard to move. I have since decided that any larger scope, I will keep on some sort of wheels to avoid frustrating me out of observing. Indeed, recently, I received a fairly hefty GEM, and quickly put some wheels on the bottom of each tripod leg. I felt liberated.
4. Celestron C5+ 5", f/10 SCT (1994)...Bought in early 1994, this scope appeared to have fine optics, and I used it to view the Jupiter comet collision. I was not at the point of being able to properly evaluate scopes at the time, but I will say that I viewed all kinds of deep sky objects with no problem including M51, the Veil (w. filter), M97, M108, etc. Since it was small, and designed to be used table-top, I used it w/o a tripod, which would have made the scope more convenient to use, had I had one. The one - arm fork did add to vibration problems. I like the scope, but quickly moved up to a C8+, selling my 8" homebuilt reflector. I think this scope probably would have made carry-on luggage on an aircraft if packed in a softcase carrier. Somewhat expensive, around $1000.00
2001 Update: Well, the above price certainly has come down with the NEXSTAR 5 available for around 900 to 1000.00. However, even less expensive and airline friendly would be a C5 OTA only with an integral 1/4-20 tripod adapter and GP/CG5 mount adapter. This is available and I got one second hand April 2001. I was able to compare this scope to the Sky 90 Takahashi OTA which of course is much more expensive (like 4X more) There are some similarities. Both are about the same size and weight, although obviously shaped differently. Both resolve M13 similarly, detect 13th magnitude stars barely, and are crisp on Mars. As expected, the C5 OTA shows a brighter overall image by a small amount, but less contrast and the net effect is a very similar image. Stars seem to be more colorful and "come to life" more in the refractor, especially at low power. I also haven't yet compared the wide field views using a reducer-corrector, but my previous experience with SCTs is that the images tend to be far worse wide-field than fine refractors. Medium and high powered views though are similar enough that one should strong considering owning this model as their carry-on scope on an airlines, with better results in my opinion than a 90mm. Mak. NOTE: Looking hard at the star test, it was fine in-focus which is most important, but I did notice an odd flaw to the star test in the parfocal test. Working outside of focus the diffraction rings showed a non circular ring amongst the other circular ones, almost like just one ring was "expanding" towards the outside of the pattern. I have never seen this before, but the in-focus performance on Epsilon Lyrae, and Mars were excellent.
PROS: Easily transportable, inexpensive, versatile CONS: Makes a good 2nd scope, not a first
5. Celestron C8+ f/10 SCT (1994)... Gathering over twice as much light, I noticed a big jump in brightness of objects with the C8+. Optically it was excellent, but again, I was just learning how to judge this. Views of Jupiter and Saturn were crisp. Deep sky was excellent from my suburban site. M1 and other harder to find Messier objects were easy with practice. No mirror shift was noted. There was vibration still noted from the dual fork arm setup, and was distracting when focusing. M46 became my favorite Messier object as I accidentally discovered its planetary nebula superimposed on the cluster. This is no carry-on airplane scope, but quite portable for any car. A bit expensive.
1997 comments..In regards to the performance of the C8+...... I often hear folks saying that a refractor will have much better performance than a C8. This is only partially true, and true for some of the wrong reasons. One reason smaller refractors show stars more as round, hard airy disks at high power is because they are just that.. smaller. The airy disk size is therefore larger, and easier to discern. Also, smaller refractors are definitely less susceptible to seeing problems, and may appear to have more pinpoint star images because of this. I have been putting scopes up to ea. other back to back lately, and this is a very important point. Also.. the quality on 8" SCTs from Meade and Celestron appears to vary widely. All 4 SCTs I have owned have been quite good, but I hear many reports of lemons. If you can't see anything beyond two bands on Jupiter at times of good seeing,you have a problem.
PROS: Excellent optics,
liberal focus travel, tried and true all around scope CONS: Bouncy on the
wedge, planetary performance not as consistent as a 5" + refractor (thermal,
and obstruction reasons)
6. Meade
LX200 Ver. 3.2/3.3 8" f/10 Computerized GOTO SCT...(1994) This
is the first scope that I began to critically evaluate. While optics were
excellent in general, I was not able to get a perfectly shaped diffraction
ring surrounding the airy disk at high power, even as skies steadied. This
is, however, an earmark of poor seeing (as I later found out with scopes
that at times had excellent optics) so I am not 100% sure that it was a
flaw in the optics or not. Anyway, in terms of operation, I found, as in
most LX200s ... it to be excellent, except noisy. I also didn't like that
it would not work on small battery operation, but relies on a 12v battery
with a converter, which goes on the fritz from time to time. The pointing
accuracy was more than adequate, except right near the zenith (in alt-az
mode). The GOTO operation (the scope moves to the object itself) certainly
did wonders in my suburban skies, where few stars are sometimes available
to hop off of, making star hopping difficult. (Terrible light pollution
to the south and east.. decent at the zenith) The best part of the alt-az
operation of the LX200 is the stability it introduces. You can whack the
scope and it will barely budge. It is heavier than the Meade and Celestron
SCTs in general (8"), but was still able to be moved , tripod and all,
across my lawn to dodge trees. Car-portable. Good price considering the
electronics.
PROS: Tried and true GOTO system, stable
in alt-az mode CONS: Less optical consistency than my Celestrons
7. Meade LX200 Ver 3.34 10" f/6.3 Computerized GOTO SCT (1995)... A bit less car portable, and also a bit less steady on the tripod due to its weight. This scope most easily would be moved on wheely bars, or any sort of dolly placed under the tripod. The additional light grasp of a 10" over an 8" isn't all that much. It does make a difference on certain objects, such as globulars which broke more readily into stars w/o straining. Indeed I was seeing about 1/2 magnitude deeper, easily, but is this worth the weight? Depends on how much moving around of the scope you are going to do and how you are going to do it. Featured identical operation to the 8" LX200. GOTO operation excellent. I never did get into CCD, or heavy duty photography with the scope, so I didn't use a wedge. Optics were excellent again, with striking detail on Jupiter noted at higher power. (However, not as crisp as later scopes as you will see) Barely able to detect Cassini division on Saturn at 5 degree ring tilt, but I could do it. Same problem with the first diffraction ring showing some spiking in focus, but out of focus star test was excellent.
Ran into a mechanical problem
with this scope, where occasionally the Dec. gearing would loosen up, allowing
for some "slop" in altitude movement up and down. This needed to be tended
to on occasion by opening everything up and playing with the gear box.
Not really what I had in mind when I bought it. This is typical of LX200s
as far as i can tell. Generally, an excellent scope, but not quite a high
precision "instrument"... yet. Meade customer support was very good, btw.
Good price considering the electronics, and the modest additional cost
over the 8".
PROS: Tried and true
GOTO system, with online support (MAPUG) CONS: Less stable than 8"
model
8. Celestron 8" Ultima 2000 f/10 Computerized SCT....(1996) This Celestron wonder has the GOTO capacity, but is very quiet, and runs on double A batteries. Problem with the scope is that balance is crucial, unlike the LX200, as it maintains its knowledge of where it is pointing even when you move it manually. The LX200 cannot be moved manually w/o it losing its place. A big disadvantage of the scope is that it needs a two star alignment, in alt-az mode, to get it even tracking, and in twilight, this can be tough. In fact, the LX200 can even be set so that you will have an approximately correct alignment, just by powering it up due south, if the scope is level. This is handy for finding planets by day, or by quickly starting to track on anything for a quick 5 minute peak if you are in a rush, and don't want to take 5 extra minutes to align.You cannot do this with the Ultima 2000. Also, the scope is not quite as stable as the LX200 8", but more stable than the LX200 10". It is very, very lightweight, and the best GOTO scope for portable travel, not quite carry-on luggage, but really good for a quick car ride to the country and back.
The reason I chose to keep
this scope over the LX200 were simply the optics. I can't begin to describe
how good they are, however, it could be just that I lucked out getting
one of the first ones around. I can detect the airy disk and first diffraction
ring in focus, out of focus star test is good (not perfect), and I split
doubles to .8 arc seconds cleanly, not messy looking. Jupiter shows detail
right down to white ovals, 6+ belts, a very clean look at the Great Red
Spot, with detail within, on Saturn... the Cassini division was more clearly
seen at 5 degree ring tilt. The scope was only a bit better optically,
but it made a difference, and spoiled me. It was better than my 4" Astrophysics
Traveler (which we are getting to) on planets, which was contrary to what
I had heard would be the case, and despite the huge central obstruction.
I have since improved upon my planetary views further, but this is the
scope that spoiled me, so that even the better refractors seemed to be
ho-hum, so far. Good price considering the electronics.
PROS: Superb optics and
great GOTO. Easy battery operation. CONS: GOTO not as good as LX200,
not as supported a product, especially with NEXSTARS coming out
9.
The Takahashi 4" FC100 f/8 fluorite Refractor APO (1996, 1998) (2): More
than 1/2 the scopes I have owned I have bought second hand. This was one
of them, and what a scope! (Actually I've owned two) This is the scope
I learned what stars are supposed to look like. Little round balls at high
power. (As I mentioned, that doesn't hold true with larger scopes whose
airy disk sizes are too small to show this unless seeing is exceptional
to the nth degree) This was my first good refractor, and I began to see
advantages and disadvantages. I owned it simultaneously to my 10" SCT,
and a Televue Pronto. This size refractor is interesting in that you can
achieve really good performance on planets and double stars, and deep sky
is just coming into clear view on some of the dimmer objects. Star test
was near perfect. Very slightly undercorrected. Second scope was better
than the first. I was able to mount the scope on a Gibraltar mount and
used it alt-az. Needed Meade rings to do it. I also struggled with it on
a bogen tripod and non-heavy-duty head. M13 split to individual stars,
and the ring nebula looked like a ring, but was not as clear as in an 8
or 10" SCT. This scope is built marvelously, although it is larger than
the more portable Astrophysics Traveler which I subsequently bought, and
less portable. The focuser on Takahashis are like no other, one of the
smoothest I have ever seen on any scope. The dewshield is very long, and
the tube beefy, you can see and feel the quality, its obvious. It is of
white color with pale lime green highlights. The finder seemed very well
made as well. Slight false color was seen on the very brightest stars only
and not at all on the planets..or moon. The latest version of this scope
is the FS-102. Relatively expensive.
PROS: Superb consistent
views all -around CONS: Too large for airline (overhead) transport
10.
4.1" A/P Traveler f/6 (3):
I bought this scope new
after waiting for 6 months. I should have never sold it thereafter. In
fact, I kissed the box when I bought a 2nd one, when it arrived! It is
a truly portable scope, and is a quantum leap in performance above the
Televue Pronto/Ranger, and similar smaller refractors. The scope's sliding
dewshield enables it to be crunched down to 19" long, and weighing only
9 lbs, it is easy carry-on luggage on an airline. I used it on a Gibraltar
mount, but it can be used on heavy duty bogen tripods with heavy duty heads,
such as ones that are geared. The 13th magnitude star near the Ring nebula
was detected with averted vision (update: direct vision later) , and M13
was substantially split (to complete individuals) with averted vision in
suburban skies . Could even see strings of stars like in the big scopes
in M13. Planetary performance was excellent, but not better than the best
8" SCTs that I have had, although it was close. The wide field of view
is something that this scope maintains despite its getting up into the
more substantial scope category of 4" and above. So, where this scope falls
short in light gathering compared to larger SCTs, and reflectors, note
that it has the benefit of 3.9 degree+ real field of view observing, taking
in M31 in just about its entirety, and both parts of the Veil nebula in
one field with a 35mm Panoptic eyepiece. The scope performs almost identically
to the Takahashi 4"., but is even more color-free. (Almost totally) The
star test on the 2nd Traveler is close to perfect, living up to the 1/10th
wave or better pledge. My first traveler was pre-interferometer, and seemed
to be at least 1/8th wave or better at the eyepiece. These scopes are expensive,
but reasonably priced considering the size factor. Larger and much heavier
than the Televue 85mm (fatter) but much better light grasp. More difficult
to mount than other airline carry-on scopes due to the extra weight. Works
well on a Great Polaris / Super Polaris mount.
6/99 Update:
Long story behind this 3rd A/P Traveler. Needless to say, the quality continues,
with reports from users
of recent-made Travelers
coming in at 1/10th wave or better. 8/99: Recently tested
against an MN71 mak-newt. Lost (by a tad) on planetary performance. However,
big step up on planetary performance from A/P's new 92.5mm "Stowaway".
Scrutinizing Plato, the
lunar crater from stable Florida skies I was able to count up to 8 craterlets.
I also made out small white ovals near the Great Red Spot on Jupiter.
6/00 Update:
Received yet another Traveler just to test, and early model. Spherical
correction not quite as good, a bit overcorrected. Nice in-focus performance,
but it was a virtual "tie" with the Yang/TMB 4" f/8 despite the 5mm extra
aperture. I placed this scope on the "Wimberly" tripod head and am pleased
to report it actually works through moderate magnification without any
problem (except not being able to reach the zenith without a "ball" head)
PROS: In case I haven't made it clear, the Traveler is currently still THE best airline portable 4" scope on the market. CONS: Still a tad heavy for certain alt-az mounts
11.70mm
Televue Pronto, f/6.8 (3): I've owned three of these scopes, and they
remain the most available of the truly ultra-portable superb quality refractors.
Each one had similar (good) optics, with ED glass, and not-quite color-free
performance. The scope showed some minor color on bright stars, the moon,
and to a small degree on planets. Jupiter took magnification up to 200x
pretty well, and deep sky views were excellent at low power. Higher power
deep sky was good too, but its hard to see much with only a 70mm when you
get up at around 100x, and beyond. M13 could not quite resolve to individuals,
but showed granulation.. and I could see down to around 12th magnitude
near the Ring nebula in suburban skies. While the scope can be used to
pick up on shadow crossings on Jupiter, etc, don't expect to see small
detail, or lunar transits. Also, the Cassini division could not be seen
on Saturn at 5 degree ring tilt. However, Mars did show significant detail
when it reached 14 arc seconds. The beauty of the scope is the 2" capability,
with a 2" diagonal and a 35mm Panoptic, both branches of the Veil nebula
can easily be made out with an OIII filter, very ghostly and beautiful.
The full N. American nebula equally as nice! Very portable with a nice
over-the-shoulder soft case. its only around 5 or 6 lbs, and is about 16"
long. A bit pricey.
PROS: Great performing very small telescope.
Well built. CONS: Definitely some false "color"
12.
7" Meade Maksutov: This is one fantastic scope. I bought just the tube,
and rigged it onto some fork arms, so I can't comment on the mechanical
ease of the LX-50 or LX200 version. However, optically, it performed very
similarly to an excellent 8" SCT. Contrast seemed higher, but that could
be because the aperture was less, darkening my suburban skies. One of my
best views of M51 was with this scope, although no spiral arms were clearly
noted in magnitude 5.3 suburban skies. There is a built in fan to hasten
cooling of the tube, but it still took a long time. Like my 8" Ultima 2000
with excellent optics, planetary views equalled or exceeded a 5" astrophysics
refractor. Globulars resolved slightly better in the 8" SCT. There is no
magic to the Maksutov design that makes it better than Schmidt-Cassegrains,
however, manufacters have an easier time making these scopes reach higher
quality, more regularly, and thus have earned a great reputation, such
as the Questars. A well figured SCT will perform just as well, but you
may have more difficulty finding one. The tube is longer and heavier than
an 8" SCT tube. Very reasonably priced. (Try pricing a 7" Questar!)
PROS: Good, consistent
optics CONS: High power views only, yet better choices for planetary exist
out there
13.
Celestron C14, 14" f/11: I didn't get much of a chance to use this
scope, but it did pull in significantly more light gathering than a 10"
SCT. Planetary views were clearly better as well, but I couldn't get a
stable atmosphere long enough to see how much better. Skyglow in my suburban
skies prevented the lower power viewing from being significantly better
than smaller scopes, but higher power views were improved, especially on
non-extended objects. Stars could be seen to around magnitude 15.0. The
Orion nebula did not look nearly at colorful as with a 16" reflector that
I would get shortly afterward. The scope is extremely cumbersome, and is
best in a permanent installation. Putting it on and off the fork arms was
a Herculian feat. The fork arms and massive tripod themselves were heavy
and cumbersome. This is not at all like manipulating the assemblies of
smallers SCTs. This scope is apparently excellent for astrophotography.
Expensively priced.
PROS: Tried and true
great all around large scope CONS: Very heavy, huge cool-down time,
less contrast than todays big dobs
14.
12.5" f/4.8 Meade Starfinder Dob: A
waste of fine optics. Not only is the base constructed poorly, wiggling,
and wobbling, but the mirror cell retained so much heat, that even after
leaving the scope outside ALL NIGHT LONG, the scope still hadn't cooled
down. Deep sky views were similar to the C14, significantly more light
gathering than a 10" SCT. Star test was excellent! But alas, with the scope
unable to totally cool, I have no proof of how good the scope was on planets,
doubles, etc. I did install a fan which helped somewhat, but wanted to
move onto something else. The scope was somewhat luggable, and could easily
be transported without any problem in my mini-van. Motion was fairly smooth
on the dob mount, and it was fairly stable. Balance was a big issue, and
I had to construct an elaborate velcro counterweight system using gunshot
bags. Reasonably priced.
PROS: Price, optics
CONS: Cool-down time, poor construction
15. 16" f/4.59 Starmaster Truss Dob: Made a good decision on this one! Sporting ultra high quality Pegasus optics, 96% reflective coating on the primary, and 99% on the secondary, this scope is amazing both on planetary and deep sky. The advantage it has over the Obsession is that the mirror is removable, and allows for easier transport. The disadvantage is that it is somewhat stiffer in motion than the Obsession (so I am told) but therefore holds balance better. Also while this scope is finished red oak, it doesn't have the furniture look of an Obsession either. The owner, Rick, is very helpful and encourages phone calls anytime. This is a small operation compared to a company like Meade, or Celestron, but that may be a plus, as Rick checks every scope out himself before it leaves. Set up time is about 15 minutes. The Orion nebula shows up with a tremendous amount of color.. not subtle. I left it in the eyepiece, nonchalantly, for my 13 year old son to see, and he wanted to know what the "green thing" was, and why it was colored that way. The Trapezium easily breaks into 6 stars, but not only that..the color of the stars is discernable. Brighter globulars are completely resolved, similar to photographs. M15, for instance, even with its tight center, was resolved almost to the center except a tight area of lumpiness in the middle that resemebled the letter "r". Stars can be seen to 15 to 16th magnitude, including the central star in the ring nebula with averted vision on best nights. Normally harder to see galaxies are a cinch, such as the NGC galaxy right next to M13. Stephan's quintet was detected as well. This all under suburban skies, limiting magnitude about 5.2. I still have difficulty with extended galaxies because of the skyglow.
Because of the ample light
gathering, using the Televue binoviewer is a joy with the scope with plenty
of light to go around, and its helpful at reducing some glare by splitting
the beam, on brighter planets. Planetary performance is out of this world.
On most nights I need to stop down the aperture to 5.5" with an off axis
mask. Even stopped down, I haven't found another scope yet that is as clear
on Jupiter. Non-stopped down is even better, but only when skies steady.
Then, Mars showed significant detail when it was only 5 arc seconds large,
not just the polar cap. Most Martian features were discernable when opposition
grew near. Jupiter easily shows its white ovals, bright blue festoons,
and multiple thin belts. Also detail can be made out within the Great Red
Spot. I have not seen skies steady enough yet to split doubles without
the aperture mask. The scope is very stable, and smooth in motion. It stays
in place when it stops, and requires a bit of a nudge to get it going again.
There may be a GOTO and drive device developed for this scope soon. Very
reasonably priced.
PROS: Great performer on all objects
CONS: A bit taller than competing models (tall person friendly)
16. Meade ETX 90mm Maksutov f/15 (2). Meade's answer to the Questar, the ETX, is quite a compact little travel scope. I have never owned a Questar. I only tried the spotting scope version (two of them) one with better optics than the other. I did not have planets readily available to me at the time for testing optically in that regard, only Mars and during poor seeing. I did not keep the scopes long enough to do them justice in a review. I will say that M13 would not completely resolve to pinpoints at any magnification, but it was just about there, breaking into that "ground sugar" look, similar to on a 70mm Pronto. Most smaller scopes of high quality show great contrast in suburban skies like mine, as skyglow is kept to a minimum. This was in great evidence on Comet Hale-Bopp which was extraordinarily nice in this scope with its pinpoint stars. Well built Maks like the Questar and ETX have a good reputation, but don't expect them to beat out a refractor of similar size. Not only is the field of view limited by the f/15 ratio, but the central obstruction is going to take at least a tad away from the contrast. I have heard the astronomical version of this scope has had some problems, with mount and drive, however, the spotting scope version, is solid enough with its integral star diagonal as far as I can tell. My flip mirror was not working on one unit, but once repaired by Meade, it was working just fine, allowing one to switch from an erecting prism, to an astromical view, back to an erecting prism (supplied). The finder was a joke, and can be tossed out, replaced by a 1x finder if you wish. Cost was quite low, especially compared to the sturdier Questar.
OCTOBER 1998 Update: I have not only received another ETX, but this one has the best optics of the bunch and is the ASTRO version. AND I COMPARED IT DIRECTLY TO THE TELEVUE 85mm (see below) I can sum up the scope real quickly. Toylike.... EXCEPT the optics. The drive works, but only after waiting for it to "take" which was awhile. The little legs work, so that polar aligning (rough) is possible. The little controls work for fine tuning dec and ra, but are sub-par quality of larger scopes. The finder is still awful, but I realized it is at least true-image, not inverted. I used a 1x pointing device most if the time instead. HOWEVER, this is not only the best ETX optics I have seen, the star test was the best of any compound telescope (like SCT or Mak) that I have ever seen. . . it was at least 1/6th-1/8th wave at the eyepiece if not better. Even the in-focus images show an airy disk and an absolutely perfect circular diffraction ring surrounding it, again, not what I am used to in a cadiatropic scope, really nice!.
I compared the views directly to the Televue 85mm apo. It was close, but it lost on all objects. I also did a similar test previously with another person's ETX. Jupiter was very sharp, and the GRS was visible. Saturn's Cassini division was discernible, but not jet black. The Televue 85mm APO showed similar resolution, at most slightly sharper, but actually seemed a tad brighter despite being 5mm less in aperture, (but unobstructed!) and the biggest difference was there was more true color saturation. Jupiter had warmer tones with the GRS looking slightly pinkish, etc. Also, I was able to resolve M15 better in the TV85 (yes, it is partially resolvable!) than the ETX at the same magnification using comparable eyepieces.
I also had the opportunity to try the ETX on close doubles. The splits were just as wide if not wider, but the excellent look of the airy disk , plus one bright diffraction ring at high power, actually hindered seeing some of the secondary stars when they were tucked close to the primary, due to the brighter diffraction ring (it can hide the second star) than what is produced by unobstructed telescopes such as the Televue 85. In other words.. yes, close doubles were split right down towards 1 arc second, but they weren't quite as clean as in the refractor.
Despite loss to the Televue 85mm, if you can get your hands on an ETX with this kind of optical quality for Meade's low price, you are doing REALLY well. The price discrepency is huge, and for the money, this is one helluva scope.
There are a lot of accessories out for the ETX now, some work well, some not quite as nice. Here is the link to Mike Weasner's ETX Supersite.
PROS: Great contrast and performance at low cost CONS: Relatively igh power only, 85mm refractor far better
12/16/99 Update (ETX - EC with AUTOSTAR) - I have had a chance to purchase the new ETX EC, 90mm and AUTOSTAR new from the store. (This is my 3rd owned ETX and my 4th tested ETX) I also equipped it with a motorized focuser, an option from Meade. I have a love/hate relationship with this cut little scope. There is vignetting on anything 26mm and above (with a 50 degree apparent fov).. but otherwise the optics are quite sharp. Star test is around 1/5 or 1/6 wave on this latest one. The f/13.5 ratio is a limiting factor to this scope. Meade ALMOST got it right, but at f/13.5, using the supplied 26mm eyepiece, your exit pupil (how large the beam of light is reaching your eye) is 2mm, which is not sufficient as a "starting point" when observing deep sky, that should be your intermediate power. Some objects therefore appear dim, and they would not have at lower magnification. They should have allowed for 2" eyepieces to solve this problem, or at least a vignetting-free system that you can use with 30, 32, and 40mm eyepieces.
Well, I mounted the ETX using
a homebrew plate so I could get it on the Bogen 410 tripod head, not much
to that..very convenient. The motorized focuser when hooked to the AUTOSTAR
(GOTO POINTING HAND CONTROLLER) is slightly inconvenient in that you have
to fish around just a bit in the menu to change focus. The AUTOSTAR itself
is overdone in it's software. I mean, there is even a listing of black
holes you can slew to. (obviously you can't see it) It almost works flawlessly,
but NOT QUITE. About 1/2 the time the alignment is slightly off, leaving
objects just outside of the eyepiece. I don't think it was my technique
either.. I think it's quirky. It's really quite amazing to see this little
scope slewing around the sky for a mere $750.00 which may be a lot to some
folk, but not to the LX200 / Ultima 2000 / and Astrophysics GTO crowd.
The instructions bugged me too, they were adequate for me, but I couldn't
help but wondering just how confused a newcomer would be when reading them,
they seem to almost assume you have bought a GOTO scope before. There is
missing information like Polar alignment, and double-star lists (would
help on certain objects to be provided with a list like in the LX200 manual)
- unless I missed it somewhere. Overall, still a great scope at a
great price, but it could be better.
17. Vernonscope 80mm Brandon f/6 refractor.. I received this scope in March, 1997, just in time to finish out Hale-Bopp. Extremely compact and well built, and with a completely apochromatic 80mm objective. Rubber armored. However, through all this praise, I have to raise some caution, as the first scope I received needed its optics replaced, and despite incredible performance in-focus, the out-of-focus (in/out) star test does bug me a bit, even with this set of optics. There is a "zonal" error evident, but there is no way I am going to swap out the optics again, as I am having performance that is right on par with a 78mm Takahashi FS78, which I had side by side with it. That's the ultimate test. Example: Multiple belts on Jupiter including the currently difficult to see Northern Temperate belts, the Great Red Spot, shadow transits (easy), Jovian moons as different size disks (not sure how that is possible on an 80mm), very clear view on Saturn with the dark shadow of the rings black as can be, & with good seeing, I am sure the Cassini division will be evident. Splits of doubles are nice, and clean, including the double-double, and Izar. I can even split them at only 70x. M13 will resolve to diamond like tiny pinpoints with averted vision in dark skies, not just a ground-sugar look. I can see to 12th magnitude with the scope in suburban skies, and may have once glimpsed the 13th magnitude star at the tip of the ring nebula, but have to confirm that.
The scope is small, only 16" long, and only 5lbs. It comes with a camera bag that can hang off your shoulder. It also comes with a 2" focuser, like the Televue Pronto, which will allow you to maximize the scope on low power. The scope works on a photo tripod. A mount for a 1x finder is included. Long focus travel means that you will not need an extention tube for straight through viewing, if viewing at infinity. The scope is somewhat pricey, and is not currently available. It is the best travel scope around based on versatility. Do not confuse this with the 1980s Brandon 80mm, or the currently available Brandon f/6 80mm birder scope (that is an achromat, not an apo) Do your homework.
PROS: One of the best airline portable scopes ever made. Color free. Reasonably priced. CONS: Optical quality varied scope to scope. Focuser not up to par.
18.
60mm f/8 Takahashi FC-60 .. This scope had perfect optics. No false
color. Incredible resolution for a scope this size. It is limited by its
aperture, showing various nebula a bit more weakly than a 70mm Ranger.
However, against the very nice 63mm Brandon, it was able to pick out more
stars, due to the incredible optics. Down to 11th magnitude. This scope,
like the larger Takahashi units has a very smooth focuser, and generous
dewshield. Very well built. Tube about 20" long. Wonderful views of Hale-Bopp,
and could make out the ring nebula easily. A bit tougher on M51, but I
could make out a double nebula. The double-double DID split, but at high
power only, over 150x. M13 would not split. Significant detail on MARS
at 11 arc seconds. Pricey for this size.
PROS: Scope is extremely
high quality CONS: Too small for any serious astronomy in my opinion
19.
78 mm f/8 Takahashi FS-78.. One of the finest scopes around, but not
really airline portable like the Astrophysics Traveler (105mm), or the
Brandon 80mm, or the Pronto 70mm. This scope showed slight overcorrection
on its star test. its in focus images were superb, with a wealth of detail
on planets, a split on M13, and the 13th magnitude star near the Ring Nebula
actually showing up in suburban skies (barely) with averted vision. I used
this scope as the benchmark for others to approach in excellence. The 1.25"
diagonal can apparently be replaced by a 2" one with some additional hardware.
Focuser, like all Takahashis was the smoothest of any scope. The Brandon
80 performed almost as well as this scope. Scope is somewhat pricey, but
not at all compared to the larger Takahashis which start running into some
serious money.
PROS: Great all around performer from
wide field to planetary CONS: Bit large for airline (overhead) portability
20.
63 mm Brandon f/5.6.. This hard to find scope, no longer produced,
was an excellent achromat showing a great amount of detail on Jupiter for
its size, and a nice view of the ring nebula. Stars were easily seen to
11th magnitude. This scope is tiny , only about 12 or 13" long, and very,
very light, useable as a finder, or guidescope. The focuser was fair, not
excellent. Some color fringing noted on brighter objects, including planets.
Very low cost for performance that isn't all that short of Televue's Pronto.
Runs under $300 on the used market. You need to figure out a way to mount
the scope, may fit in some finder rings.
PROS: Super-small scope
with very good performance CONS: Not built that well
21.
100 mm Lzos f/10 Astro-Rubinar 1000. This is an odd Russian Maksutov
scope to say the least. It focuses mainly by using it like a telephoto
lense, turning the lense left and right. its optics were excellent, but
showed less contrast than the Brandon 80mm. It only worked well with its
own limited set of eyepieces, which sat in a variable barlow diagonal.
The advantage of this scope was its price, also it apparently would make
an excellent telephoto lense in itself. A beginner could use this small
scope on a photo tripod, and with its eyepiece collection and zoom capability,
have a complete range of magnification. Runs even less the full blown ETX,
but is available in spotting scope format only.
PROS: Price, resolution
CONS: Hard to use, contrast wasn't great
22.
Televue Ranger 70mm f/6.8 Refractor. This scope is similar to the Pronto
in size, weight and performance. Indeed it is the same basic system. However,
one can only use 1.25" eyepieces on this scope, (2" is a bit of overkill
with a 480mm focal length anyway) and it has a helical focuser, which requires
some getting used to, but was very smooth. Still, it performed just as
well if not better than my Prontos. A great portable scope at a lower cost.
For performance details, see the Pronto.
PROS: Cost , also see
the PRONTO above CONS: No 2" focuser
23.
120mm f/8.5 Astrophysics Star 12 ED This great value scope featured
a nearly color-free doublet back in the early 1990s. Performing wonderfully
on both deep sky and planetary, but not quite to the level of Jovian detail
as my superb Celestron SCT (which has unusually excellent optics.) Nevertheless,
in a side by side with the formidable 6" f/12 Intes Maksutov, it showed
better contrast, and thus saw a bit deeper into the sky , down to 13.5,
nearly 14th magnitude in suburban skies, roughly 1/4 magnitude better than
the Intes. Also, Jovian detail was similar to that 6" scope. The dumbbell
nebula was extremely pretty with detail on both axis set against a pitch
black sky, even though there was some minor skyglow in my darker suburban
setting. The 13th magnitude star near the tip of the ring nebula was easy,
even seeable with direct vision. Perfect field size with a 55mm Televue
Plossl on M31. M13 split, but, not as impressively as larger scopes. Last
sold for under $2000, with prices flirting with that mark again today on
the second hand market.
PROS: Great buy
CONS: You can do better (optically) with a 5" in today's market. Slight
color
24. 6" Intes f/12 Maksutov (2). I have also owned the f/10, which performed similarly. A great value scope, perhaps because it is Russian, performing as well (in many regards) as a 4.1" Astrophysics Traveler refractor on most objects, but with a much smaller potential field size. (due to f/12) The scope is sized for portability, and can be used on certain Bogen tripod/head combinations, and can be carried onto airlines. M13 splits, but not as nicely as on an 8" SCT. Jupiter shows a wealth of detail, again short of a truly excellent 8" SCT, or my (current 11/98') 7" Starmaster. Still white ovals, lunar transits, and the Great Red Spot are all visible, easily. Jovian moons are very clean, round multi-sized disks. 13th magnitude stars are easy, testing near the ring nebula, but it probably would take a pitch black sky to see to 14th mag. star nearby. 2" Crayford focuser, with limited focus travel. Can be tricky on some eyepieces. (Focuser with 2" diagonal worked quite well on this latest scope) Scope runs under $900.00!! new.
1998 update: I tested this
scope extensively against the 7" starmaster with Zambuto optics. The 7"
reflector had more light scatter, in fact much more, which was a problem,
when viewing planets. (darker field surrounding the planet more obvious
on the Intes, like a refractor) However, the Starmaster was much
more contrasty and clean looking on the planetary views, within the planets
themselves, relative to the Intes. (and brighter, and more colorful) Also,
deep sky views were better, in the reflector with M42 showing hints of
color more readily and just generally showing up better both from a contrast
and light grasp point of view. The Intes however is remarkably light, and
easy to carry onboard an aircraft, making it a great alternative to a 3
or 4" refractor to bring overseas or cross-country. The carrying handle
makes it "goof-proof" when mounting. Detail is significantly higher in
the Intes on planets than 3 1/2" high quality scopes such as the TV85,
the Meade ETX, etc as well. Again, planetary performance was close
to the A/P traveler... with the slight edge going to the Intes. Not as
good planetary performance as the 5.1" EDF A/P refractor, nor the 7" "planetary"
reflector.
PROS: Great buy, great
optics CONS: High power only. Construction okay,
but not great I like Mak-Newt performance better
25.
50mm f/8 Takahashi FC-50 .. Again, like the 60mm, perfect optics, no
false color. The scope is pretty amazing, but limited by aperture. Like
its larger brothers it has that well built tube, large dewshield, and super
smooth focuser. (1.25") It worked very well through 170x, especially on
the Moon and Jupiter. Jupiter showed belts clearly, but not quite as well
as on an 80mm Brandon up against it. This scope also just barely split
the double-double up over 150x, and did split IZAR. M31 looked classic
with M32, and M110 showing up, but it all looked dull and uninteresting
compared to larger scopes nearby. This would make a super finder, guidescope,
or portable scope. its only 15" or so long and extremely lightweight, just
a pound or two. Similar to the Brandon 63mm, but better built, and pricey.
Hard to find as well.
PROS: Fabulous tiny scope. Dynamite
"finder" CONS: Too small in aperture for anything serious, perhaps
even guiding
26.
Celestron C102 (Made by Vixen, non-fluorite version). This 4" scope
easily showed the Great Red Spot on jupiter, cleanly and widely split the
double-double, and gave a superb view of M27, and M31. Pinpoint star images.
However, I found that even in stable seeing conditions, I was not making
any further gains above 200x (this may sound like a lot to ask, unless
you own a Takahashi, or other quality scope that takes 75x/inch easily)
Jupiter view was a bit better than the 80mm Brandon (but not much), not
nearly as good as the 8" Ultima 2000. There was slight "color" with this
achromatic scope, but it hardly annoying, and indeed almost in the semi-apochromatic
category. As good, or better color correction than the TV Pronto. Note..
Scope is fairly large, at f/9.8, but not particularly heavy. 1.25" Focuser,
smooth. Construction was good, but also not Tak. quality.
PROS: Great scope, great price
CONS: Some "color" , not up to par with fluorite and ED line
27.
Palermiti 43mm mini-scope. (2) Mike Palermiti from Jupiter, Fla. is
constructing a high quality finder that can double as a mini rich field
telescope. It was available on Astromart. It literally fits in one's pocket,
being 4" long and weighing less than some eyepieces. A f/3.1 the scope
is not showing nearly as much resolution as the f/8 50mm Takahashi..but
it is a fraction of the cost. The pocket size scope is exhibiting slight
color especially at high power as well, despite its apochromatic designation
by the designer. It is not slick in construction materials, and to focus
one much push-pull your eyepiece. However, you can use this as a crude
guidescope, and I have succeeded in making a pair of binoculars out of
them. It takes 40x easily, and shows Jupiter not only as a disk, but does
exhibit some banding. Its double star resolution seems to be around 3 or
4 arc seconds, unable to resolve the double double's tight pairs, but able
to break the Trapezium in Orion up at only 28x. On nebulosity it is fairly
dim, but shows much greater resolution, even at lower power than binoculars.
For instance, M37 is greatly resolved. M31 AND M32 show up with a hint
at M110. M42 (orion) stands out with a nebula filter to it full extent,
its shape clearly seen up around 20-28x. The ring nebula can be viewed
as nebulous, not just star-like. M27 did show its classic apple-core shape,
especially when used as binoculars. The scope is very picky as to which
eyepieces it likes and doesn't like. For some reason the 30mm Ultima eyepiece
worked at 4.5x, and an astouding 11 degree field with hardly any coma.
I am still scratching my head about that one. It also loves the 7mm Nagler,
but works horribly with the 19mm Panoptic. It does not take to barlows
well, and has limited focus in-travel.
PROS: Smallest scope
in history? CONS: No focusing method other than push-pull. Odd construction
28. Takahashi 5" f/8 FS-128 (2). While I was expecting a lot from the 5" Tak, I really didn't expect perfect optics, as there was some spherical aberration on the FS78, and FC100 that I previously owned. I had found a perfect star test on 2 FC60s, and the FC50, I assumed it was aperture related. However, just about a perfect star test is what I got when testing this particular FS128!! (and a 2nd one I tested too!) The views are outstanding, with ultra-crisp Jupiter and Saturn views, (the Crepe ring more noticeable than with any other scope, Cassini division black as night) and exceptional contrast on all objects. I easily picked out 6 stars in Orion's trapezium., 5 (star F) right away, the 6th (star E) with minimal to moderate effort. Even in suburban skies (l. magnitude 5) the sky appeared black enough to give awesome nebula views. I had the scope right up against an excellent 8" SCT (Ultima 2000, see above), and the SCT seemed just under the TAK at times of steady seeing in its performance with planets... Meanwhile, deep sky was more effective with the 8" SCT, but the 5" contrast almost made up for the lack of light gathering (really!) I am not sure how much this was due to the fact that the sky seems blacker with smaller aperture, and how much was the scope itself, but at least in suburban skies, while you can see less of M31's nebulosity, what you could see was more enjoyable at the same magnification. Due to the focal length of 1040, you can reach 2.6 degree fields as opposed to the 8" f/10s 1.4 degrees. I was almost able to take in all of M31 at once, and yet with a high degree of resolution. The moon was significantly "whiter" in this scope than in the SCT...due to the better contrast.
The tube is short enough that it can take a Televue binoviewer in straight-through mode without a barlow, allowing for wide field viewing. I would highly recommend this as an alternative to a 4" super giant binocular. (note..recently tried the Astrophysics Zeiss/Baader binoviewer, and it works in the diagonal position too w/o needing a barlow!) An important factor in deciding on this scope is the fact that many poor seeing nights (when the atmosphere is turbulent) affects larger aperture, before small. I have confirmed this time and time again. With this scope, therefore, you have more good-seeing nights available to you for observing planets, the moon, etc. One note.. even though it has the APO tag, on absolute brightest stars (not the moon or planets) I can detect some false color, more so than many triplet APOs.
FC125 Feb., 2000: Just received the legendary FC125 that belonged previously to Mike Harvey and Markus Ludes that was generally considered the best planetary performer at a previous WSP. My curiosity got me on this one. I would agree with Markus that Jupiter and Saturn against such a dark sky does give off a more unreal, 3-D like experience. The FC125 of course is Takahashi's earlier offering with the fluorite element on the inside. The star test is quite good, seems to be 1/8 wave or better... like the FS128. I was able to discern more in moderately good seeing with the 10" Teleport (see below) due to it's aperture, I'm sure.. but this scope does offer up some of the best contrast I have seen between the object and the sky. Without them side by side, I can't say whether this is truly better than the newer FS128s, as it is reputed to be. Sure wouldn't be surprised though. Scope came with 4" focuser, reducer, rings, and 11x70 finder and bracket. Takahashi grey highlights compared to the normal lime green.
PROS: These scopes are optically superb for wide field right down through planetary at a very "serious" level CONS: Can't think of any negatives
29.
Bausch and Lomb 4000, 4" SCT f/10: This is a truly portable scope with
a couple of problems. The scope is around 14" long, and only weighs 2lbs
12 oz. It is available on the used market only... and I was sold the spotting
scope version. This means it comes with a 1/4-20" hole on the bottom, and
easily fit onto a Bogen tripod..which was overkill for this scope. This
scope is so small and light it can be fit into a small backpack, if you
are flying. The scope comes with a built-in 1.25" diagonal which you screw
on the back. It does not seem to be able to take standard 1.25" diagonals.
This is unfortunate, since the one provided has limited clear aperture,
and will work best with 20mm eyepieces and lower. After collimating, star
images were fairly tight, and M31 looked quite nice. However, on a star
test, I came out with 1/2 wave based on Suiter's book (finally I had a
start test that I could figure out!) There were no further optical problems
that I have heard about with this scope from other users such as pinched
optics, or astigmatism. Jupiter did reveal both the SEB and NEB, but images
were best using 10-20mm eyepieces, leaving a pretty narrow range. This
is a very affordable guidescope, and would be a great travel scope, considering
its aperture is fairly large compared to refractors of this size, and its
weight is even lighter than a Pronto. Scope perhaps a tad larger than an
ETX, the ETX has the sharper optics. The finder on this scope is better
than the one on the ETX.
PROS: Small
CONS: Optics not as good as ETX
30.
6" Meade f/3.6 Schmidt-Newtonian: This is a very popular scope on the
second hand market, no longer being produced by Meade. They really should
think about re-releasing it. A similar scope was made at f/5, and they
had an 8" f/4 at one point. The corrector plate makes this otherwise coma-prone
"fast" newtonian into a useable wide-field scope suitable for fast photography,
and wide field views similar to fast 3-4" refrators (in terms of true field
size). It sports a focal length of only 549mm. The Celestron Comet Catcher
(see below) is another scope of this approximate design, but has some key
differences. This scope is riddled with positives and negatives. Firstly
it is extremely well built, very rugged (although I hear that the corrector
plate can break on shipping if one is not careful) and offers an incredibly
wide panoramic view through its 2" focuser. The scope is about 18" long,
and 12 lbs, so it cannot be tripod mounted, but needs something on the
order of a Super Polaris Mount. Widefield views were good with lots of
light throughput noted, but planetary performance was almost non-existant,
perhaps due to its large secondary obstruction (very large). The secondary
was built into the corrector plate, but you were able to view, like a Newtonian,
from the front. The particular scope I had did not reach focus unless you
pulled the eyepiece way out, which probably hurt visual performance, cutting
off the light path, but was probably done with photography in mind... to
allow for various in-travel options that may be needed. The double - double
was an easy split at high power, but not at all clean looking with a lot
of light put into the diffraction rings surrouding the airy disk. The Orion
nebula was nice, but the Trapezium was sloppy looking. Overall, an impressive
wide field photographic and visual scope, but not near refractor performance,
and too heavy for my taste.
PROS: Fast, fast scope
CONS: Optics not great at all
31.
Celestron Comet Catcher, 5.5" f/3.64, Schmidt-Newtonian: This scope
was tested within days of the Meade f/3.6 above. The similarity and differences
are important to deciding which scope might be right for you. Unlike the
heavier, sturdier Meade, the comet catcher was made with a tripod user
in mind. A sturdy Bogen tripod, with a sturdy head could handle this scope,
weighing in at 7 lbs, and 19" long. I had one of the orange tube models,
from the early 1980s. After I tested it, I have heard of widely varying
quality scope to scope., which is discouraging. The corrector plate was
much thinner, and the secondary obstruction smaller than the meade. Focus
was achieved by moving the secondary back and forth (smooth focuser) rather
than the normal in-out of the eyepiece. The focuser however is only 1.25"..
I specifically measured 33.5mm, which is suitable for visual work, and
photography too, but has reportedly caused minor vignetting on the 35mm
frame. However, a very nice adapter came with the scope that allowed the
camera to be attached directly to the 33.5mm opening, rather than having
to use it through the eyepiece holder. (The eyepiece holder screws off).
Views were sharper than through the Meade, with stars more point-like,
but still not nearly as sharp as in an 80mm Brandon refractor. Planetary
views were better than expected through 100x., with both the NEB and SEB
on Jupiter extremly easy to see. M31 was particularly interesting as a
test subject, showing off neighboring M110 more easily than the 80mm refractor.
M42 was nice with the Trapezium a bit more clearly split than in the Meade.
The double - double was not readily able to be split in this scope at higher
power, which may be proof that its not whether or not you can split the
stars, but how clean the split is that is important. This scope makes a
low-cost alternative to a wide field refractor with a great deal of light
gathering for a scope with a focal length of 500mm I did not find this
scope terribly durable, but the trade-off was its lack of weight, which
makes it suitable as a carry-on item on an airplane!
PROS: Cost!!! Fast
scope!!! Small!! CONS: Optics could be better. Construction
could be better
32. Vixen 90mm fluorite 1980s version (sold as Celestron): (1997) Jay Reynolds Freeman had raved about this scope, so an Astromart ad caught my attention. The price was so high that I knew either the seller was overpricing it, or he knew he had something special. Before I get to the incredible performance, let me go through the negatives. The focuser is a bit flaky, with some sticky areas, but this older version is 50mm wide, so it accepts 2" eyepieces when used with the Lumicon adapter (current version of this and the 102mm apparently do not have true 2" capability) Also, the scope is so lightweight, that I wondered if it is built as sturdily as the similar sized Takahashi FS78-FC76. Also, I am having trouble seeing how many baffles there are, I think the TAKS may have more. Now.. for the performance. Unbelievable. its not that this scope is outdoing my larger aperture scopes on planets, its that I am even having this discussion at all! This is, after all, only a 90mm scope. Yet the performance on the planets is big league, with the Cassini division on Saturn for instance available each and every viewing session even in mediocre seeing (1997). The seller indicated that Cassini was visible last year (1996) which would put it at or above the A/P Traveler in planetary performance . .. and the reason I bought it. The star test is perfect, and colorless inside and outside of focus, as were the images of brightest stars. NO COLOR. Despite my claim of excellence in the second set of optics on my Brandon 80mm... this scope is in another class. Deep Sky views appear roughly 25-50% as bright as the 80mm, at high power, (which somewhat exceeds the math) but that's hard to quantify. SIX STARS were viewed in the Trapezium in Orion, although only with straining averted vision. I did know where to look, but at least one of the stars surprised me by being tighter in than I had expected. Jupiter was very crisp. . . but the lack of light gathering will likely hinder high power performance on very subtle features. I could make out some festoons, the GRS was not available, but the dark red ovals at longitudes 270/288 were very crisp and readily visible. Banding on Saturn was a cinch, and as I mentioned the Cassini division was a snap from 120-270x. Daytime peformance is crisp through 400-500x. What I am most impressed with is the cleanliness of the airy disk. Very little energy goes into the diffraction rings at high power-in focus-star testing, meaning my splits are very clean, and dimmer than expected stars are seen. Even with a high deck of clouds, I was able to split M13 to individual stars for instance, limiting magnitude was around 4.3. This is a super-lightweight scope (maybe 7 lbs) that works very well on the Super Polaris, which is overkill, but can even work with certain bogen tripod/head combinations. It is 32" long with a 4" dewshield which can be removed during travel. Careful airline portability is an option if one gets a nice case. I have no idea if the current units (80-90-102mm) have this kind of performance. I know of 2 other 1980s units that do. The only down side is the aperture, the Takahashi 5" will resolve much more of the tough star clusters, and probe deeper and show more color (real color, like on the Orion nebula). An 8" SCT , same thing. For a small scope though, this optics are unbeatable, and will allow some serious lunar/planetary observation akin or at least approaching the big boys.
2001 Update: I have received two more of these fine refractors and have thrown them against the Sky 90. One has what looks to be approx. 1/6th to 1/8th wave undercorrection , and the other perhaps 1/9th wave overcorrection, nearly perfect. Both had similar views to the Sky 90 using it's "extender-q" option. Performance was almost identical. Still testing..
PROS: One of the best performing 90mm
scopes ever. CONS: Bit large for airline (overhead) travel
33. Orion Telescope (Telescope and Binocular Center) Short-tube 80mm refractor, f/5 (2): Unbelievable value. Costing as much as a "finder scope" in itself, this scope is tremendous for the money. If it looks like Vixen, and acts like a Vixen, it MUST be a Vixen? No, the optics at least are supposedly made in China. Hmmmm. Mechanically, the scope seems to be made by Vixen, correct me if I am wrong. That is, a super-smooth focuser (better than on my expensive Brandon 80mm) , lightweight, sturdy construction (15" long, no more than 3 or 4 lbs) , and a Vixen-style dewcap, and vixen-style quick release finder.
Optically its quite good, but not at all in the class of the 70mm Pronto/Ranger or Brandon 80mm. The scope comes with a 45 deg. erect image diagonal, which you should DEFINITELY put aside for astronomical use. . . unless using it as a finder. It also comes with a small finder, which is easily removable (too easily.. the seller I bought it from already removed it and kept it). A nice 25mm Kellner eyepiece is included, which I did not use for testing. In my eyes, the cost of the finder, eyepiece, and diagonal amounts to around $75 discounted (or second hand) which means you are getting the scope for a whopping $175!. The scope has a 1/4-20" threaded hole on the bottom, and works well on a bogen tripod. It takes a standard 1.25" star diagonal, and with a focal length of 400mm, will serve up a wide 4 degree field of view at 12.5x, through a 32mm plossl. Star test was actually pretty good. False color was quite noticeable on all bright objects, and I believe caused a contrast problem when not as noticeable. However, at low to medium power this scope really works well. Not as sharp as the 80mm Brandon, but still quite well resolving clusters like M37, quite crisp on the Trapezium of Orion, with lots of nebulosity. A split on Epsilon Lyra at 100x and over (yes.. its splits the double-double!) but not as cleanly as the 70mm Ranger. The planets were quite good to over 100x, but a contrast was less than on the other refractors, even though resolution was quite good. However, almost like a Veil was thrown over the planets at higher power up over 150x which was distracting, and in fact, while you couldn't see this on deep sky, I think it (invisible "veil") was responsible for the lack of crispness at high power on deep sky objects as well, worsening the view compared to the expensive models. This scope was less contrasty on Jupiter than the 64mm Baby Brandon too, but has more light gathering. . . on the other hand. Also, especially at around 50-100x planets gave a crisp appearance, with a clean view of Saturn's rings, although the Cassini division was suspected but not confirmed. Stars did not show a perfect airy disk at high power, but medim and low power views showed stars pretty pinpoint-like indeed. The sky was not as black as on the better scopes. Coma was noticeable near the edge of my Panoptic and Ultima eyepieces, but not too much. Photographs from the previous own er of this scope on deep sky were fabulous, except for some small coma towards the edge of field. its an f/5 scope, so you have one helluva 400mm telephoto lense if you use it prime focus. Overall, a great star-party knockaround scope, a superb finder, or guidescope... and serious enough for very real astronomical use. This scope on a sturdy tripod is what every beginner should own rather than a dept. store telescope. It is a finder in itself, and coupled with a 1x reflex pointing device would probably be able to get most anyone "into" astronomy right away!
33b. Celestron is
currently importing the same exact scope , except it mates to it's included
Equatorial mount. Also a good value, the Celestron Firstscope 80 WA (wide
angle) is 350.00 or less for the package, which includes everything except
the is no finder. (the scope itself makes a nice finder at low power)
PROS: Cost, size
CONS: Optics could be better
34.
The Intes MK-65 f/10. This scope is an earlier version of the MK-67.
While I continue to be impressed with the pinpoint stars, and high, clean
looking resolution on doubles, this particular model had two problems that
I noticed. One, its helical focuser was not as convenient as the currently
offered Crayford with the MK67, and forces you to use 1.25" eyepieces on
this already limiting 1500 focal length. Two, and this is a more universal
complaint, there was not as much (true) color on the Orion nebula as in
a 16" reflector stopped down to 6.4" (off-axis, unobstructed) or a 5" Takahashi
refractor. I noticed this before with a C14 compared to the 16" reflector.
While this seems to be mostly a light gathering issue, perhaps there is
some issue about the coatings on corrector plates ...or perhaps contrast
is coming into play in some way as well, involving the secondary obstruction.
I can tell you that the 8" SCT does deliver a nice amount of blue-green
on the Orion nebula.
PROS: Sharp optics
CONS: More recent models more convenient to use, see above
35.
The Palermiti 60mm f/2.8 miniscope. (1997) The scope is very
small, a mere 7" or so, and fairly lightweight at just about 3 lbs. It
was originally designed as a scope for a medium format camera. It should
work well for photography as it does "zoom", with a twist of the front
cell, its focal ratio varies from f/1.4 to f/2.8. Mechanically, the scope
is great as a guidescope. At f/2.8 there is plenty of focus travel. Focus
is achieved by smoothly rotating the very front of the dewcap. The scope
takes 2" accessories, such as a 2" diagonal and focuses well for almost
all 2" eyepieces. The only problem with the scope is that when using eyepieces
10mm and below, it simply didn't work well. I showed a Spherical abserration
in the star test of over 1/2 wave (that's being kind) and chromatically
it was a mess. This was supposed to be an APO. Mike Palermiti explained
that this fast scope was falling victim to the it's extremely fast focal
ratio, and was passing his bench tests with flying colors. While I sent
this scope back, I miss it already and wish I had kept it as a guidescope,
if for nothing else.
PROS: Very small CONS:
Optics not at all what I expected
36. The
Celestron/Vixen Fluorite 55mm., f/8 Another scope that I doubt
is still available, this is right up there with the 90mm Vixen Fluorite
and the Takahashis in quality. Stars are superbly sharp and color free.
There is a hint of resolution on M13 and even M5 despite the tiny aperture.
I could even (barely) make out the Cassini division on Saturn, which was
weird. The aperture is limited, and even bright stars don't look bright,
but as a guide scope, or portable wide field scope .. pick up one of these
if you run across it. About 16" long, only a couple of pounds heavy. Star
test near perfect.
PROS: Great optics,
tiny scope CONS: Too small for anything serious. Not built
as well as the Takahashi 50 and 60mm
37. The Televue 85mm APO 85mm f/7. (2/98) By odd coincidence I obtained the first commerically available (available via a dealer that is) Televue 85mm which is coming out in greater supply in the Spring of 1998. The scope is heavier than my Brandon 80, and weighs approximately 7-8 lbs. (I misplaced my scale!) It worked well on a heavy duty bogen tripod and head, but was a bit less stable than the Pronto on the same mount. The scope is 19" long and fits in the old Televue Oracle case which was supplied until the new case becomes available. This also fits numerous eyepieces. The case is just under 24" long, but quite thin, and worked well as carryon luggage. The scope is extremely well built, almost overbuilt, and sturdy. It is basically an oversized Pronto with a super-smooth focuser, as good as the Takahashi focusers. The size of the scope is almost as large and heavy as an Astrophysics Traveler, but not quite. The scope is quite pricey. However, it has a lot of advantages. It has the standard Televue ring holding it, which allows for flexible add-ons such as the adapter plate for a GP mount, or for a "Starbeam" finder, or for a piggypack camera mount. Also, since the tube is longer, there is more balance flexibility than with the Pronto as one slides the OTA up and down in the tube for optimal balance.
My impressions so far are quite positive, but the star test does not come up to the Vixen Fluorite or Takahashi as best I can tell. Small undercorrection, and another aberration was noted. Al Nagler claims to put a lot of work into optimizing the in-focus performance more than the star test, and that this is what counts. I had this scope down in Aruba with me for the eclipse of the sun. The prominences were extremely detailed, and I haven't seen a photo yet that has come close to capturing that detail. Deep sky performance was impressive, and reminds me of the 90mm Vixen Fluorite. That is, M22, M4, M13, and Omega Centauri all split to the core with averted vision when the nebulas reached dark portions of the sky. Eta Carina looked wonderful, but not as nice as in a nearby LX200 (duh!). I did have the scope up against a 90mm ETX and the performance on deep sky at high power was about identical. However, it achieved wide fields and wide exit pupils, bringing life to objects that the ETX could not pick up because it was strapped to high power. (at f/14). In fact, I could get a 4.5 degree field out of this scope, sharp to the edge with the 55mm Televue plossl..in the ETX, we maxed out at 1.25 degrees. Consider the exit pupil was over 7 with the Televue 85mm, while with a decent apparent field of view size, the best you can possibly achieve with the ETX is 3mm exit pupil. The bottom line..much brighter images are possible, when going wide-field, especially useful in conjunction with and OIII or UHC light pollution filter. This is why I highly recommend the refractors over the ETX/Questars. On Eta Carina for instance, I could out-do the ETX just by reducing my magnification. It was remarkably improved, and somewhat depressed the ETX owner. (although he ordered a Traveler I understand!)
The scope indeed is APO with green/purple seen in and out of focus on Venus only. Even during the star test on bright Sirius color was not seen. Similar to the Brandon 80 in that regard. The sliding dewshield is a plus, and the scope has an optional screw on filter that acts like a daylight filter to protect the objective. This 95mm threading will also allow it to be used with a screw-in solar filter whenever they become available. I have put the scope right up against the Brandon 80 for a brief comparison and found that it performed slightly better due to either better transmissiveness or the larger aperture. I was able to see more deeply, with a few stars more evident that were marginal in the 80. Also, I got a better split on Izar, which is perfect and very colorful in the TV85. The Brandon 80 however is a faster scope, better suited than this one for photography. Testing the Televue 85mm on the planets was a pleasant surprise, and is dealt with in scope #40 below, the Bizarro version. The TV85 (bizarro version) in fact far surpassed the University Optics 80mm (below) in brightness and color correction, leading to a better Jovian view, despite the high quality of the UO scope in general.
I did get a chance to compare this scope to an excellent Meade ETX.
4/00 Update: COMPARISON of the Televue 85mm to the Takahashi FCT76.
Here are some pics through the TV85, when I first tried my hand at ccd.
PROS: One of the best easy-to-buy airline portable scopes (overhead) Easy to get repaired if needed (Televue) CONS: Can't think of any offhand.
38. University
Optics f/7 80mm Achromatic. I heard so much about this scope from enthusiastic
users, it was good to see that they were right! This scope certainly performs
nearly as well, if not as the Televue Pronto/Ranger series, and yet is
less expensive, even though discontinued. It is a no-frills, Aluminum scope
of 80mm aperture, f/7. It is just under 19" long, and just a couple of
pounds, maybe three, it's lighter than the Pronto by about 1/3. The scope
attaches to a tripod with it's integral 1/4-20" holes (3 of them, choose
one for balance) but does not come with mounting rings. It is not nearly
as well built as the Pronto, and Ranger, or the Brandon 80mm APO f/6 (1997
version, non-birder), and it's focuser is not as smooth. Nevertheless,
it's a great achromat. Showing a nearly perfect star test, despite color
noticed outside of focus, it's optics are superb. The GRS was noted (but
not clearly) on Jupiter along with sharp contrasty belts. False color fringing
is noted, on brightest stars, and planets, maybe a little bit more than
the Pronto/Ranger, much more than the Brandon 80 apo (which appears color-free)
A friend has reported splitting the trapezium in M42 at 16x with this scope
as well, not an easy feat. This scope is of far more quality, optically,
than the more-affordable Orion short-tube 80mm, but is larger. IN A SIDE
BY SIDE test against the new Televue 85mm APO, this scope showed far less
light gathering and far more color, despite the otherwise excellent performance.
PROS: Great performance for price,
league above Short-tube 80. Small, airline portable (overhead) CONS: Some
color. Construction decent, but could be slicker.
39. Astrophysics 130mm EDF f/6. (1998) Well, I waited for the scope patiently, but a friend came through and sold it to me second hand in June 1998, just months after he got it! Worth the wait. Superb star test. Incredible performance and versatility. On my first night out Jupiter was crisp as could be, and a ccd image revealed much detail. No false color noted on the star Enif, or on Jupiter. A 27mm panoptic yielded a wide, pinpoint star view. Only 28" long, and 15 lbs. The perfect 5" refractor for both high power and low. A 5x televue powermate barlow gave me as much magnification as wanted.
Have tested the scope at
300x on Jupiter with wonderful results. The Great Red Spot pops right out
at you. Oval BE was clearly noted (merged ovals bc and de) along with the
new disturbance in the southern equatorial belt, extremely clear. The double
barge near Sys. 2 longitude 270 was ridiculously easy. A televue 85mm was
nearby and could pick most of this up as well, but not as clearly. See
LATEST
JUPITER picture with this scope for an example of the features discerned
(the CCD is showing similar features to what I have detected visually,
but with more contrast) Saturn's Cassini division is very easy (1998) and
one can just about follow it almost all the way around in front. The Crepe
ring was visible as well. The planetary views in general very similar to
the 5" Takahashi. Although I missed a deep nightime sky in a test, with
just a bit of twilight brightening up my limited magnitude to around 4-4.5
I was still able to make out NGC 7331, 7332, and 7662 very clearly. 7332
is not that bright, and was pleased to see it in the 5.1" scope, especially
under those conditions. Later, on a subsequent night views of the Veil
nebula and M31 were quite pleasing, with those perfect pinpoint stars sprinkled
across the field. Here are
some pics through this scope.
No "CONS" to this scope
40. Televue 85mm "Bizarro" f/7. (1998, 2000) I don't understand quite how it happened, but I managed to get one of the first Bizarros sold again (like I did with the TV 85). It's an interesting scope made specifically for use with the Televue Binovue. The scope includes the Televue Binoviewer (without the optional-use barlow), the carrying case, a 2" star diagonal, and a special 2-1.25 adapter with built-in corrector lense..that one will pop their binovue into. The corrector lense seems to require racking in focus a tad, and also lowers magnification by a hair. The scope weighs maybe 6 lbs., and is exactly 13 5/8th inches long not including the diagonal. The carrying case is 24" long though, and includes a slot for the Binovue. You could easily fit this scope in a large camera bag, if you take it with you without the Binoviewer on an airplane, etc. This is exactly the same as the TV 85 but 5" shorter, so the nice tube ring, and durable finish, excellent focuser, dewshield, etc, are all the same.
Views were fabulous at both low and high power. Low power using two 30mm Ultimas through the Binovue was better than any binocular I have viewed through in edge performance, color correction, etc. Light gathering after splitting the beam is roughly similar to a pair of 20x70 binoculars. However, one can jack up the magnification, and in fact, bring it all the way beyond 200x easily for high detailed planetary/lunar views. (see below) The optics showed a near perfect star test, on the order of 1/8th wave or maybe even a bit better. Izar was split at only 85x, and Jupiter showed so much detail that I was a bit startled. White oval BE (merged ovals BC and DE) was detected, along with the rift in the Southern Equatorial Belt. The dark red ovals (barges) in the Northern Equatorial Belt was easy. The Great Red Spot was visible too, along with the Cassini division on Saturn. This scope showed no false color even on bright stars, nor within the star test (extrafocal). This confirms that the planetary performance is as good with the Bizarro/TV85 as the Vixen 90mm fluorite, an outstanding scope, but the Vixen is less rugged. Due probably to the aperture, this scope generally performed better than my Takahashi FS78 did as well. (for instance more resolution on globulars) The televue 85 and Bizarro 85 are also more color-free than the Takahashi doublets. (although the Televue's are not as thoroughly baffled)
Televue is marketing the scope as Binovue-specific, as it is shortened five inches to accommodate the greater in-travel needed with their binoviewer. They prefer that you use it that way, and if you really plan on using it primarily without the Binovue, or at high power, that you consider the Televue 85mm, instead. That said, it is normal for me to go off on an adventure, and this is what I did to make the scope more versatile: (Televue reminds me that this could theoretically compromise scope performance)
Firstly, to reach high power, one method was just to use the little Celestron Ultima barlows on each side of the binovue (pictured at the top of this page) and I popped 7 Naglers into them. This brought me to 170x.
Secondly, I had an extension tube laying around that worked just fine (it is a 2.25" extension with a long barrel, perhaps by Lumicon) to bring the focus distance back out to use the scope as a regular Televue 85mm. In order to do this, I had to pull the extention tube out somewhat, and "back out" some eyepieces too. At close distance even that wasn't enough to bring the scope to focus, but for astronomical use, it's just fine.
Lastly, this method of reaching focus can also be employed for magnified binoviewer use, if you have the Televue 2x barlow, which unfortunately is NOT supplied with the scope. You can't really get over 120x or so, without doing this. You see, with the barlow tube and lense in place (like one normally uses the binoviewer when bought separately) the focus is back out 5 - 5.5", the normal position of the focuser. My spiffy solution was to use the cell of a 1.8x Televue Barlow. Employing that cell by screwing it onto the end of the 2x barlow tube, which then screws into the Binovue, I was able to magnify a resulting 2.7x (the 2x barlow magnifies 3.8x in the binoviewer but is "parfocal") which brought the focuser in a little bit , meaning that I still needed my extention tube, but had less balance difficulty, and didn't have to "pull out" eyepieces, etc, to reach a nice focus place. If I've lost you, email me about this.
Of all the scopes tested, I would recommend this short version of the Televue 85, or the regular Televue 85 or the Astrophysics Traveler for airline portability.......
05/2000: ........Or, the
A/P "Stowaway" for that matter, but the Stowaway (f/5 92mm A/P scope) is
not really available. I received another Bizarro after trading mine back
a few months ago. The second bizarro's star test is not quite as perfect,
but still very good. In-focus
no problems at all. Using the .8x Televue reducer/corrector coupled with
a Lumicon T to 2" adapter, I can use those two in unison by placing them
in after the diagonal, but before the eyepieces, and reach focus single-eyepiece
with this 3.75" thing sticking out of it. Only a bit inconvenient, and
it works great at f/5.6. M13 completely resolved, easily, similar views
to the most recent Televue 85, scroll up for more info. on that.
PROS: Only 13 5/8" long! Airline dream! Also for performance, see Televue 85mm! CONS: Hard to reach focus single eyepiece, with extentions.
41.The 12.5" f/4.8 Portaball from Mag1: Without a doubt, this is the most "fun" telescope I have ever owned. However, like anything, "fun" comes with a few compromises, and I'm not talking about the slightly high price tag (it's worth any extra $$). The Mag1 Portaball is so well thought out, and put together, it's mind boggling. Even the packaging was first rate. The scope consists of a painfully constructed ultra-smooth "sphere" which holds the primary, six very easy to assembled truss poles, and an upper tube assembly. The sphere sits on a base, and like an Edmund Astroscan, you can pan the scope directly to anywhere around the sky AND YOU CAN ROTATE the scope as you do so.. giving you a sense of freedom you will never find in any other scope, as you match the eyepiece view to your eye-height. The scope is built to height, so at the zenith, you have a good view, as you do virtually anywhere in the sky. I found myself mostly wanting to view from the left side of the scope, unlike the normal right side that I have been viewing from through dobs, due to the more convenient (higher) placement of the Telrad that way. Movement is SUPER SMOOTH, in fact, it presents a small problem in itself. You see, balance is a big factor with this scope, and while balance is set for a wide range of eyepieces, the necessary smoothness of the way the scope moves, does create certain limits. Firstly, you must use the TELRAD (1x pointing device) or the scope will be backheavy. Secondly, you cannot balance with a loaded binoviewer easily, unless you put a cloth over one of the pads on the base, or setup the sphere with less wax applied to stiffen the movement a bit. HOWEVER, balance can all be pre-set from Peter Smitka, owner of Mag1 ahead of time, if you know you will be using these heavyweight eyepieces and/or accessories, but it is more of a problem if you switch back and forth from light to heavy. Thirdly, with the above in mind, if you are balanced to offset heavyweight eyepieces (like mine is to some degree) it is a bit difficult to change eyepieces without losing your place unless you get around that with something like a 2" paracorr remaining in place to keep the front end loaded while the eyepiece is out of the holder. Lastly, you can easily bump the scope out of place, and it is unwise to use this scope at a starparty full of kids or newbies!
The optics that came with the scope were unbelievable. Mine came with Pegasus optics, they are now sold with other (superb-Zambuto!) optics, guaranteed better than 1/20th wave p-v at the wavefront!! My mirror was rated at 1/28th wave p-v on the wavefront, which is ridiculously well figured... but the set of testing techniques used, while useful for comparison purposes with other mirrors finished the same way, usually falls short of those numbers when these mirrors are put under an interferometer.
One problem..the optional light shroud when in place, seemed to sag with the dew, and cut into the light path. This can be avoided apparently with a certain spray according to Mag.1. Also, the lack of a rocker box makes this scope super-portable, and able to sit on the front seat of a small car! However, the weight is a bit much to lug around the lawn from place to place, but you can purchase a moving cart to shuttle it around. One needs to handle the sphere EXTREMELY carefully, unlike a dob, if you bump the outside of the sphere, you can affect the smoothness of movement and incur a costly repair. Lastly, you CANNOT use digital setting circles with this scope, so get ready to brush up on your star hopping.
Negatives aside, the scope
moves so easily, that manual tracking is effortless and extremely enjoyable.
In fact, I would run out to the garage just to pan the scope around INSIDE
just for the fun of it. The focal length of roughly 1500, coupled
with an aperture of 12.5" is very versatile. (They are now made at f/5)
For instance, I was able to view nearly all of M31 in one field, and yet
the light gathering ability is much larger than a typical rich-field refractor
at the same magnification. Thus.. I had a nearly photographic view of M31
and was so easily able to pan around the galaxy due to the nature of the
scope. I also had my best view ever of the Veil Nebula due to this combination
of large field size, and light gathering. This of course holds true for
any of the fast, high quality mid-size dobs, but is even more noticeable
with a scope like this which pans in any direction. I recently
had a tremendous view of Saturn and Jupiter in the scope. Jupiter showed
great detail, beyond my excellent 5.1" EDF Astrophysics refractor. Saturn
was so well detailed, I made out the thin band along the equator, and the
mysterious Encke complex roughly 1/2 way into the A ring. (not the
Keeler division all the way out, I'm not THAT good!) Logistically, I am
not likely to be able to keep this scope due to my heavy use of a binoviewer
(not only is the balance situation a bit inconvenient, but the binoviewer
orientation would have to change every time I rotate the scope) and
my reliance on Digital Setting Circles for hard-to-find objects. However,
this is THE scope I would have chosen for myself when I was 19, and frustrated
by my heavy GEM and 8" Newtonian, which helped get me OUT of backyard observing
for almost 20 years. It's just a joy to use, and I HIGHLY recommend it.
There is also a shorter 8" version now available. Kudos to Peter for creating
such a well made product for us to enjoy!
PROS: Joy to use, breaks
down small for car transport CONS: Long cool-down time. No encoders
possible
42. The
7" f/5.6 Starmaster Classic: (1998)
A very interesting story
about this telescope. I bought it third hand, knowing it's great reputation
and paid nearly full price. It is no longer sold new, as Rick Singmaster
elected to put his full energy into his larger scopes. It last sold for
around $795.00. While it came with a 2" focuser, it was a helical focuser,
which is virtually impossible to use with a binoviewer (think about
it), which I use quite often. The scope has smooth motions, but is just
stiff enough that I can see using it with a binoviewer such as the Televue
Binovue outfitted with the new 2x magnifier (a regular 2x barlow would
produce 3.8x magnification). This will allow it to reach focus in the scope.
Anyway, I decided to replace the focuser with one of the JSLs that
Rick puts on his larger scopes. In addition, while I found the planetary
performance to be outstanding, in fact, on par with the 5.1" Astrophysics
EDF on Jupiter, I found some spikiness on one side of focus in the star
test, and sent to the mirror to Rick to double check it. After "real-time"
updates via email on how he was making out, he confirmed that the scope
was performaning wonderfully in-focus, but seemed to have a flaw in the
star test. (turned out to be a wide turned edge) Rick immediately agreed
to get me a new mirror, this time from Zambuto for the scope at a very
minimal charge. Re-coated and all. This I felt was more than fair, considering
it was already performing better than I had expected in-focus anyway.
The scope consists of a thin, lightweight, but sturdy tube, painted black on the interior and a glossy sprinkly kind of black on the exterior. The cell with the 7" mirror seems well ventilated, and is easy to remove. The scope comes with a Telrad 1x pointing device. It's rocker box and base, are a beautiful red oak, similar to the finish of a red oak floor. The scope's bearings are also mounted amidst a red oak finish surrounding part of the tube. The movement was not quite as smooth as the 16" dob, but pretty close. Up/down and around .. initiation does not take a lot, and once you get it going, movement is stiff but smooth, just the way I like it. I did need to put a knob on ground-facing side of the upper part of the tube to make moving it easier. The scope is very stable, with hardly any time needed to settle down after giving it a knock when planetary observing. The scope only comes up about chest high, and sighting through the Telrad is a pit of a pain. One must be sitting down to use the scope, unless you like crouching. The scope is ideal for children of all ages though. In fact, this is THE dob for youngsters who want a first scope as far as I am concerned.
Planetary performance in the first set of optics was outstanding. (see above about star test) The white ovals within the southern equatorial belt of Jupiter broke down very similarly to that of the 5.1" EDF astrophysics refractor. I also had my very sharp Televue 85mm out at the same time on this night of good seeing, and indeed it was no match for the greater aperture of this scope... and of course, as you know, I am VERY impressed with that Televue 85 for it's size. I didn't do all that much on deep sky yet, waiting for the new optics.
Portability is the key reason why I plan to keep this scope. It takes seconds to break down, seconds to set up. It fits in the front seat of a car. I did this on Saturday 10/3/98 as an example, for a quick and dirty collimation and mini-observing session while I was waiting for my son to come out of party. I only had 30 minutes.. but the quick setup time allowed me to be up and running in seconds.
I received the new mirror
on 10/2/98. It is the same brand of mirror (Zambuto) that Rick sold his
last 7" scopes with...including the very last 7" scope that was delivered
to a friend on Wed. 9/30. Since I replaced the focuser, I had a heck of
a time collimating all weekend 10/3-4. I finally got it right on 10/4.
. and tested the scope 10/5. The star test at the eyepiece is quite good,
seems about 1/8th wave, implying a 1/16th wave primary p-v, wavefront.
It may even be better, still checking. Much improved. Saturn was a bit
crisper (only when skies steadied for small moments) than my 5.1" Astrophysics
EDF refractor. I expected it to be a close call with the 7" coming out
ahead. It was. The Great Red Spot and vicinity also showed a tiny bit more
detail than the 5.1" EDF refractor, but as in the past, up against other
scopes, the refractor held steadier, sharper views longer in the mediocre
"seeing" conditions. Given perfect seeing, the 7" I do believe has the
planetary edge. Deep sky shows more light gathering, than the 5.1" refractor,
but a tad less contrast, the result is pretty similar performance overall
between the two scopes. I had less trouble getting a 5th star in the Trapezium
with the 7" starmaster in mediocre seeing, but, more testing is needed
in non-moonlit skies on how the two scopes measure up. Stars are
pinpoint, similar to in the refractor. . . when skies stabilize. Bottom
line, if this scope comes out again, or you can get it 2nd hand.. it may
be sensible to consider it over the more expensive refractors if you are
a visual observing only, and don't mind manually tracking. Performance
is very similar, & portability is greater although fit and finish is
certainly not in the same league as a fine APO.
PROS: One of the best
performing scopes ever in the 7-8" category. CONS: Tube currents frequent.
Could have been made even more transportable with some extra thought. Could
have used additional baffling to match the incredibly good optics.
43. Starmaster 18" Stablite with GOTO drive: (12/98) This scope is a panic. Imagine an 18" dob accurately slewing across the sky and landing on your selected object! The Starmaster 18" GOTO is not without some limitations, but it is very easy to use, and convenient for visual observing. I received the scope and drive in fine condition, but the connections involving the RJ-11 jacks were not working, and Rick Singmaster waisted no time sending me new cables to get me up and running. He even provided customer support at all times of day on the weekend I first received the scope, and seemed generally "bummed out" that I hadn't got it working right out of the box. First the basics:
The Stabilite (Pegasus) 18" mirror came with an excellent figure, according to the documentation. While I have only had a night of "fair" seeing so far, performance on Jupiter has been quite good, but I can't verify just HOW good until I get that "special" stable night. Like the 16", nebula are detailed, and easy to find, but low surface brightness objects are washed out in my suburban skies, so that you can see them, but nebula filters become important with this size scope in non-dark sky sites. Stabilite mirrors are more air than glass, and thus cool down right away,and keep thermal equilibrium more easily through the night. There is no doubt the Stabilite is working. Taking the scope outside from 55 degrees in the Garage to 25 degrees outside, it takes about 1/2 hour or perhaps even less to fully reach ambient temperature from what I can tell from the figure of the mirror changing. In fact, it comes to equilibrium so fast, that I have quickly been able to determine that the mirror is slightly overcorrected, but I haven't quantified it yet. This quick cool down has allowed my star images to be consistently "tight" compared to the overly long time it took to reach that point in the 16" when bringing the scope out into the cold..
The scope looks and acts exactly like my previous 16" f/4.6 scope. It is f/4.2 so it is roughly the same height. (f/l 1925mm, as opposed to 1865mm on the 16") It works the same using the Sky Commander DSCs alone, but when you turn on the GOTO drive, all you have to do is hit "GOTO" on a separate control box, and the scope automatically counts down to zero in both azimuth and altitude on the Sky Commander unit. It runs on a fairly standard 12v 7ah gel-cell, similar to what I already had for other devices. This will last for a few hours minimum if fully charged and not too, too cold outside. Working the initial alignment is exactly like using the Sky Commander DSCs solo since that is what the drive works off of, so I won't go into it here, but once the scope hits the object.. it goes automatically into TRACKING mode. The speed of the scope slew is fast, and it's VERY quiet, nearly inaudible. Rick put a little spacey "jingle" inside the control box which plays when it reaches the object to let you know that the drive is even in there and working. The scope then tracks along. The object drifts a little at first after centering it, then it stabilizes, so much so that I was able to take some short CCD photos with the scope (see http://www.weatherman.com/tak.htmbottom of page) However it still jumps around enough that it makes CCD work difficult without a slow guide speed (see below)
If you wish to move the scope
manually, you just have to disengage the clutches, the scope WILL NOT lose
it's place since the encoders are not built into the motors. This is a
disadvantage in that the pointing accuracy is only 1/3 of a degree. However,
it is a huge advantage if you would like to manually slew around for awhile,
then go back to tracking or GOTOiing. You can switch speeds from TRACKING
speed to CENTERING speed, with a more formal "guide" speed on the way from
Rick down the road for those wishing to try out CCDing with this scope
even though it wasn't built for anything but visual observation in mind.
The Stand-by button is great.. you can hit it mid-slew and everything will
come to a halt, good if you are about to hit your garage or your car with
the scope, etc. (or if you are about get knocked off your ladder!) I really
like this system because of it's simplicity and highly recommend it. If
you know the sky commander, you'll be comfortable with the drive within
an hour. It is pricey though, adding $2000 to the price of the scope.
PROS: Fabulous scope, optical
wonder. Short cool-down time (stabilite) CONS: GOTO system
works well but could be more exacting.
44. Celestron
C9.25" Optical Tube Assembly: I had high expectations about this unit
from Sky and Telescope (both reading it and what they told me personally),
and my previous good luck with the Ultima 2000, and with reports from the
web and incoming email. Generally speaking Celestron has been putting
out better optics in the past couple of years from what I understand. I
have not been disappointed. Indeed I obtained, second hand (what else is
new) the white-tube version of the C9.25" sold in Japan. The tube weighs
about 19 lbs, and is easy to weild. I purchased from Celestron the dovetail
Losmandy plate that allowed me to put it on the Astrophysics 600E mount
The out of focus star-test (ala Suiter) was one of the best I have seen
in a compound telescope, although not quite as good as much current ETX.
I'd say it is at least 1/6 wave at the eyepiece. Stars are pinpoint, and
detail was discerned on 5 arc second Mars, but I have yet to run into an
evening (Mars is in the morning) steady enough to judge it's planetary
(Jovian) performance (same trouble I am having with the new 18", can't
get the "seeing" stable enough to keep the planetary images crisp enough
to evaluate. HOWEVER, one can tell the optics are quite good. Contrast
is great, galaxies stand out against the black background, and star images
are very, very tight (Polaris and it's companion are fantastic!)
and the Trapezium in Orion clearly, easily, without any effort, shows the
6 stars. Detail within nebula is very pronounced, and in a 2
minute test CCD photograph of M82, much detail was discerned. My particular
unit has plenty of focus travel and a digital counter which help a lot
with the CCD photography (starlight express ccd,
see todphots.htm)Other notes.. no appreciable image shift has been
noted (very slight). Collimation has remained right-on. Anyway, I am eager
to observe more with the scope, and will report back.
PROS: Superb performance all around,
can match the best 6" refractors on planets. CONS: Relatively high
magnification only. Typical SCT woes such as long cool down and great susceptibility
to seeing. .
45. Astrophysics
155mm EDF f/7 Initial testing of the scope is very encouraging. Again,
tested my standard summer objects. M13 resolved a bit better than the 7"
starmaster, which actually is quite a feat considering the starmaster's
recent performance against other scopes. However, on the Ring Nebula, the
ring itself was a bit more pronounced in the 7" reflector. However, the
field stars (surrounding M57) were just as easy , if not easier in the
6" EDF. In fact, the 14.2 magnitude star in the Ring nebula sequence was
quite easily placed with averted vision without any problem, DESPITE a
gibbous moon just over the horizon. Star test was excellent, among the
best I've seen, must be 1/10th wave or better. No false color noted. Focuser
is smooth, new baked on enamel finish looks a bit more durable than the
previous finish, but isn't quite as good looking. Scope was fairly stable
on the 600E mount. Jupiter performance is outstanding. Definitely competitive
with the 18" Starmaster stopped down to 6" (which to my (and everyone's)
surprise previously beat everything I could throw at it) I am still comparing.
I am really looking forward to the head-to-head evaluation of those two
super-scopes. Here
are some pics. through this scope
CONS: None
46. "Homebrew"
6" f/5 airline portable scope. After designing a scope of decent aperture
that can make it as carry-on easily on an airplane, I decided to build
a prototype of the final version (the final is being built with the help
of Michael Spooner and his incredibly well-made mirrors) I got hold of
a starsplitter mirror used in their 6" f/5 scopes, this is NOT what they
are currently using in their larger scopes (Zambuto). The good news is
that the 6" f/5 portable did work as planned. The nesting tube design fit
in a medium size camera bag. The bad news is that the mirror, while okay,
did not perform all that well on planets or double-splits, or even globulars...I
could beat it with my best 4" refractor.
7/99 Update.. Michael
Spooner helped me refine the design, and supplied a well made 6" mirror.
He basically built the scope in a homebrew fashion with a 2" helical focuser.
We used a 1.3" secondary mirror. The two tubes that "nest" are roughly
8" long by 7 and 8" wide. They do fit right into each other securely, good
for airline travel. the bar that connects them pops onto a tripod or on
the Telepod. I prefer the tripod with geared head. (bogen 410?) Views are
very simlar to the A/P Traveler on both deep sky and planets. Brighter,
but the refractor's contrast seems to equal the playing field. Also, the
refractor has a small edge at low power, while the reflector at high power
in terms of sharpness. Scope easily shows the wide Cassini division, plenty
of detail on Jupiter, even some within the Great Red Spot, but falls short
by a fair margin of the 7" Starmaster/Zambuto scope. It works as intended
wonderfully, but is a bit "shaky" still. This may lead me to re-build the
scope someday down the line with the same optics.
PROS: 4" refractor performance in low
cost package that goes on the plane! CONS: Shaky on the mount as
it was built. Helical focuser a bit of a pain.
47. Lomo-Astel
f/6.3 rich field scope. This is an interesting russian scope in that
it is one of a kind. It is built EXTREMELY well, and is VERY short. It
can be carried in a small camera bag and is just light enough to work on
virtually any kind of tripod with it's integral 1/4-20" mount. The scope
is shaped unusually, tapering towards the eyepiece end. The helical focuser
internal to the scope is smooth as silk, and allows for abundant focus
travel. If the diagonal is trimmed just a bit (this was done by the previous
owner) the MX5c CCD camera can reach focus even with it's 1.25" adapter
in place. I was also happy to see that the 1.25" diagonal that screws onto
the unit sported full clear aperture for a 1.25" device, unlike some other
russian diagonals I have seen. Unfortunately, the scope was built to work
with this particular diagonal only, so if you have another you would like
to put on for some reason, you are out of luck. I did not get any of the
photo-accessories that apparently one can get with the scope. The scope
worked well at low power, and was crisp on the moon through 65x +. False
color was not particularly bothersome (in fact, minimal) on the moon, but
I would still not classify this as a semi-apo as it has been touted, since
there was significant "color" on the planets, and in the star test, and
on bright stars. The star test was slightly better than a nearby Orion
short-tube, but on Mars, the views were much the same, detail was difficult
to make out with Mars only 12 arc seconds large at this time. (Seeing conditions
were adequate). Spherical aberration was corrected to less than 1/4 wave.
Another negative was that there is some brightening by day on the inside
of the tube that shows up if you don't put your eye right in the center
of the eyepiece. Lastly, the scope could use some sort of home-made dewshield
as the objective is close to the front of the scope and will dew up easily.
This does make for the wonderfully short size however. While I would not
rate this on par with the Ranger or Pronto, it is even smaller and more
portable, and just as rugged. It is also less expensive, especially second
hand, selling for $300 or so on the 'net, which is one great deal.
PROS: Size CONS:
Optics
48. Intes MN56 5" f/6 Mak-Newt. I'll be honest, I was pretty shocked by this scope. I had it right up against the A/P Traveler on a night of superb seeing (very steady skies, best for judging relative planetary performance), along with 3 other scopes too. I have not been very impressed by some of the Russian scopes. As an example, the Lomo-Astel 80mm was nice, rugged, and portable, but optically not at all outstanding. Internet Telescope Exchange (Bill Burnett) sent the MN56 to me with the help of Mike Palermiti (optical certification of .97 Streul, 1/8th wave) and Markus Ludes (supplier) to test against an A/P Traveler apo with better than 1/10th wave optics. I had the option of buying the scope, but chose to give it to Ed Ting to continue to test on deep sky. I understand this scope is available from a few dealers in the US.
Planetary and lunar performance was simply outstanding, seemingly similar in performance to my prior 5" A/P edf, and 5" Takahashi FS128. That's better than I expected, and even better than Markus Ludes expected. For instance, the (superb) Traveler, a 4.1" apo, showed 4 craterlets in Plato on the moon, but they were easier to discern in the MN56. Jupiter's festoons were visible in both, but again, less effort needed to be applied to see them in the MN56. Saturn was just a bit crisper as well. However, the scope could not match the 7" Starmaster / Zambuto optics. In fact, all scopes on the field performed by order of aperture on this night. 4' Traveler/5" MN56, 7" Starmaster/Zambuto, C9.25" Celestron SCT, 18" Starmaster/Pegasus . Ironically, the 4" had the best star test, 1/10th wave or better. The MN56 appeared to be about 1/9th wave to me, but by certification was 1/8th. The Starmaster 7" is around 1/6 to 1/8th (at the eyepiece, certification much higher on the mirror, but not by interferometer) The 9.25" is about 1/6th. The 18" is about 1/5 or 1/6 at the eyepiece. (again higher by certs) Yet, as expected, each larger scope was able to out-do the next one smaller, finer details on Jupiter. In the 7" starmaster 5 craterlets became visible, and even more discernible in the 9.25" . Jupiter in the 18" showed the most detail of all, down to very small features within the belts.
The instructions were excellent
as supplied by ITE. The optical certification matched performance. However,
it came with a 2" Helical focuser which worked quite well, but seemed to
shift the image a bit left and right as I focused, perhaps I was doing
something wrong with the "quick-focus-adjust" sleeve (draw tube)
that is integral to the helical. Because of this sleeve, however, there
was abundant focus travel. (picture it, the sleeve slides in and out for
rough focus, then the helical unit is turned for fine focus) It's a nice
focuser in general, despite being a "helical". The finder that was supplied
easily snaps on and off the scope in a dovetail style. Furthermore, there
are TWO places that the finder can go, making it very convenient (two dovetail
accepting brackets, for piggy-back mounting of a camera, etc) However,
the focus on the finder was too "loose", and easily fell out of focus.
Also, the fit and finish of the scope was nice, and rugged, but wasn't
very "slick". Who cares for $799? What a price for this performance! The
only "down side" to getting this scope is in terms of portability, it's
size. It is lightweight, weighing maybe 10-12 lbs, but is way too long
for "carryon luggage" on an airlines, being over 2' long. Like a 5" refractor,
it is just too big to be used that way. HOWEVER, since it's performance
is more akin to a 5" than a 4" refractor, it is really a moot point. This
is a superb instrument, even at only 5" aperture in it's own right, but
doesn't fit in the super-portable class. I'm eager to see how Ed
Ting makes out with the scope for the remainder of the review. NOTE: The
light weight makes it suitable for almost any equatorial mount.
PROS: Price and optics CONS: Size
and weight and viewing position
49. The legendary Astrophysics "Stowaway" 90mm f/5 apo. Well, I had to pay dearly in trade and cash for this scope, but it is a great education. BTW.... It is actually 92.5mm, f/4.9. I have tried it now on deep sky and planetary and can report that while excellent, it still runs short of the Traveler, as expected, as the "best" airline portable refractor. Only a few dozen of these were made, and it is unclear whether more will follow, although I am told that a longer f/7 model may come by 2002. The scope is only 14" long, and weighs 6.5 lbs. It balances well on a Telepod, Gibraltar, or tripod, and comes with a 5" bar attached to the Traveler-like thin rings with a 1/4-20" hole in the plate. Apparently there is a 7" slide-bar that can be purchased so that it will easily connect to a Telepod, upswing head, or Gibraltar more securely. The scope is pure quality. The focuser works so that on the left is coarse focus, on the right fine focus. The coarse focus is not as smooth as the Traveler 4.1", it's a bit "jumpy". However, the fine focus is marvelous, so good, that I didn't even vibrate the scope using it at high power! It is white in color, crinkle finish, with a nice "carry-on" case. Unlike the Televue 85mm, it does not have an easy way to attach a 1x finder, which was an oversight. The dewshield also, does not extend far enough out to prevent dew formation on heavy-dew nights.
Optically, the scope is performing a tad better than the 85mm from televue, but not up to the Traveler. For instance, M13 is completely resolved, but I had to use a 3mm Radian eyepiece to best bring out its splendor , and I had to wait quite a while to be dark adapted. I can do this more easily in the Traveler. The Televue 85mm I can do it too, but can't hold the resolution as long as I could in the 92.5mm. Similarly, the 13.03 magnitude star that I "suspected" next to the ring nebula in the Televue 85mm, is easily visible with patience in the 92.5 Stowaway EDL using averted vision. It was there, but not as obvious as the 4.1" Traveler. This was all done in mag. 4.9 suburban skies. On the planets, the great red spot was clearly visible, but slightly more detail was discerned in the 105mm Traveler. On Plato, on the gibbous moon, at least one craterlet was EASILY detected, in fair seeing, while it was somewhat more of an excersize in the Televue 85mm.
There is no scope quite like this out on the market. (As of 2001, the Takahashi Sky 90 is similar, but a doublet) At f/4.9, clean views across the entire field of a 22mm Nagler.. the field of view is HUGE. In addition, it is capable of high power performance. (Some coma, as would be expected, is exhibited as stars soften towards the edge of field in many eyepieces...such as the 22, 27, 35 panoptics) To boot, it is only 14" long, compared to 19" on the Televue 85mm (f/7) but is about the same size and weight as the "bizarro" version of the Televue 85mm. HOWEVER, the focuser has been adjusted so that if you buy the Zeiss / A/P / Baader binoviewer, you will reach focus without the barlow, or so I am told. I once gave Al and Dave Nagler over at Televue a hard time for not attempting to make a scope with focus travel that could accommodate both binoviewer , and non-binoviewer use. However, note, that part of the reason is that the Zeiss binoviewer has a built-in 1.25X magnifier that adjusts focus travel a bit. This scope will not work in "right angle" format with a Televue binoviewer, without the Televue 2x magnifying special - barlow.
8/2001 Update: Managed to get hold of another "hard-to-find" Stowaway for comparison against the Sky 90 (Takahashi). The Sky 90, in the process of being improved in design (call Texas Nautical, Land, Sea and Sky in Houston for details) , does not hold its collimation very well, while the Stowaway does. The star test seems better on the Sky 90 parfocal, but in-focus I can determine no meaningful difference in performance. In viewing deep sky and planetary.. the Stowaway maintains the slightest edge in star detection and planetary performance, and less "color" (although both scopes excel in that regard, particularly considering the Sky 90 is only a doublet.) The Stowaway DOES work well with the Takahashi Extender - Q which miraculously, on some eyepieces, completely cleans up the coma and edge of field problem. For instance, using a 22mm Panoptic there is no vignetting and sharp stars across the entire field. 27mm Panoptic exhibits some vignetting, but the 50 mm Takahashi eyepiece has no vignetting and sharp stars across the field. This is similar to the performance enhancement using the Extender Q (1.6x) on the Takahashi, however, the Stowaway needs it even more due to the focal length of only 450. Thus, using a 3mm radian as an example, one can bring the magnification to 240x which is perfect for the maximum to use for this scope. I prefer this to barlowing.
No "Cons" (except the cost to get it
2nd hand, and lack of availability)
50. 10" "Teleport" with Zambuto optics: My wife told me that the UPS man dropped off the new scope in the garage, but when I opened the door, I saw nothing. I looked harder. . . Nah.. that couldn't be it over there in the corner, could it"? Yup, the 10" Teleport, developed by ATM extraordinaire Tom Noe, is one compact scope. This relatively expensive 10" is extremely well built. I wish such careful design would be employed in more commercially available units. It has a telescoping struts, that is..truss poles with a permanent shroud that allows the scope to open to a full size dob, or close up to a compact box that easily fits in the passenger seat of most any car. (I even locked it in with the seat belt!) The mirror was jarred loose during shipping, and needs recoating, (UPDATE: 12/99, now done, great service from Tom) but otherwise, I was able to test the scope with no problem. Optically, the Zambuto mirror has been dynamite. The star test is the best I've seen of any reflecting scope. The Jovian views are superb, easily detecting ovals BC and FA nearing the GRS. The planetary views do fall short of the 18" Starmaster when skies are steady. The image is noticeably brighter than the C9.25" SCT. In fact, I confirmed this as "fact" rather than just "impression" when doing CCD photography on Jupiter. Vega, although so bright, focuses to a near "point" with the 22mm Nagler. The 14.2 star near the Ring Nebula was visible head on, no averted vision needed. Averted vision brought out the 14.6 mag. stars near the Ring in suburban heavily light polluted skies. (not my usual observing spot, worse). M13 was completely resolved, but even at low power. I also detected NGC891 under gibbous moonlight. (12/99 UPDATE: Was able to detect the spiral dark lanes in M51 in suburban skies)
The scope moves smoothly, and has many special features. However, unfortunately, it is not meant to be setup on grass, a strong limitation of the scope. (It becomes "tippy") (12/99 Update.. I asked Tom to fix this with higher legs at the bottom of the base, and it has mostly cured the problem!) As mentioned, the scope folds down into itself when loosening knobs on the struts. The entire upper tube assembly fits down into the lower tube assembly which is permanently fixed inside the dob base. I have tried to design a scope like this myself in the past, but this is a true "class act". Fitted with the electrical package, the scope sports an internal fan (this all runs on C cell batteries) and an eyepiece dew remover system, and a heater for the secondary. Setup time is about 3-5 minutes, more than the advertised "1 minute" when you include collimation, and fiddling with the struts to get them to extend properly. The scope is very similar in many ways to the way the 7" Starmaster (and probably the new 10" starmaster EL) feels in it's use, but is smaller than the Starmasters when it is closed up..and much easier to transport. (since the starmaster breaks down into two pieces, and this only 1) There is an internal "flip-out" 1x pointing device. Very well thought out. Counterweights are provided to balance your particular eyepiece set, and you can get away with binoviewer use, even without a barlow (but that will produce some vignetting) in terms of weight (by counterweight) and focus (by extending the struts several inches under full extention) It is very versatile. The 7/8" to 1" thickness mirror (mine is 7/8, most 1") cools down rapidly, in most instances it will probably cool within a half hour. The focuser is a 2" helical, so that it will help the "fit" when closed, but it is a super smooth helical that allows fine focusing. The scope is fitted with a great Protostar secondary, very easy to adjust, and an eyepiece drawer ready-for-you-to-customize, which slides out of it's base. There are also internal tightening screws, easy to access, to tighten up the friction on the altitude bearings. Viewing through the scope would typically be in a seated position.
There are a few small problems with the scope. The most annoying is the actual placement of the focuser in relation to one of the struts. My nose actually bumps into the strut when trying to observe. It's not a big deal, I just have to shift my head position, but it is a bit annoying. It only happens on short profile eyepieces...and is eliminated if you use the parracorr (recommended) in between. In fact, Tom (12/99) updated my scope so that the focus position was moved out slightly to help with this minor problem. Also, I have suggested to Tom Noe, the scopes creator, to mark the struts so that you can more easily reduce the extention of the truss tubes (struts) when setting up to allow for numerous eyepiece combinations, ccd photography, or binoviewer use. You can do that the way it is, but one has to mark off spots on the struts with a pen to figure it out correctly. I also would like to see the scope grass-compatible. (it is now , 12/99.. he probably will start to ship them out this way) Lastly, the light shroud is really cool in how it automatically folds up when closing up the scope, but it does allow in light from my garage to some degree.(12/99 Update: Tom has provided me with an extending lightshield for the top of the scope that may well solve that problem) Overall the scope is a simple technical marvel, the best from a renowned Amateur Telescope Maker now gone commercial. Tom Noe's email is: tomnoe@wt.net
12/99 Update: I have decided that based on the small footprint of the scope, superb optics,smooth motions, and service.. that if I had to keep only ONE scope, this would probably be it! I have also determined the best low power eyepiece for the scope based on focus position, size, weight (balance), performance, and exit pupil is the 22mm Panoptic coupled with the 2" Parracorr. Really works with incredible sharpness. I tested it along with the 22 Nagler (would have to lower struts to reach focus with the Parracorr) the 27mm Panoptic (exit pupil large enough that there is a slight lack of clarity compared to the 22mm probably due to my own eye aberrations even with glasses) and the 24.5mm Meade Superwide (nice, but same problem as the 27 Pan, plus the edge sharpness is not all there with that eyepiece (as noted in the superwide review I made). If you want to be the envy of your astrobuddies, this scope is the one for you.
PROS: Superb optics in super transportable scope. CONS: Helical focuser a bit hard to get used to. Also, I'm a bit clumsy with the extending poles
51. The 8" Portaball, Custom 2" version: (PREVIEW) I have to hand it to Peter Smitka, I told him I wanted a 2" version of his 8" Portaball, with an undersize diagonal, and he came through. In fact, Mag1 instruments and Peter really "make" this scope. It is so slick, and yet custom made with one man behind each unit. This is the antithesis of buying from a larger company where one has no idea where "the buck stops". This scope impressed (understatement) me in it's ease of movement even more than the 12.5". It's a tiny scope broken down, just a tad too large for carryon luggage on an airline. The scope consists of the base, which can be placed on any surface, the "sphere" which includes the mirror, the truss poles, and the upper tube assembly which nests into the sphere for travel. Using a full thickness Zambuto mirror, f/6, the images are outstanding. I can't wait to have this out side-by-side with my 9.25" SCT, I believe so far from what I've seen it is performing at or beyond it on most objects. Planetary resolution is excellent, pin-point stars that look indistinquishable from refractor fields, the performance is excellent. There are several strong points to this scope, and a few negatives, and I plan to go over all of them carefully in the next couple of weeks, planning an update to this page shortly.......
11/11/99: The Portaball comes optionally equipped with an electrical package. This will prevent dew from forming on the secondary, which indeed ended up coming in handy. It also provides power to the cute little 1x Rigel Quickfinder, and to a fan which cools off the battery more quickly. With the fan on, images were disrupted, so once the mirror cools, turn it off. Also, an illuminated "dot" can illuminate the primary's center, but that is not needed if you wisely use a laser pointer for collimation. I would have liked to have seen a built in eyepiece warmer as well.
The biggest advantage to the scope is the ease of movement, which really does put the whole scope out of mind while star hopping, there are virtually no limitations in movement. You can stiffen up or loosen movement using various waxes or polishes such as RAIN-X. Additionally, the base can be placed on any surface, unlike a regular dob. You can even put the base onto packed snow! Star hopping is very, very enjoyable with this scope, as it not only moves up and down, but spins in it's base as well, so that you can pretty much keep your eye at one level as you move the scope around, you don't have to adjust your chair if you "point high" or "point low".
It took almost an hour to cool the scope down a couple of dozen degrees, with it's full thickness mirror, but this experimental 2" version of the 8" portaball does have a larger battery which may be retaining some heat, and Peter is looking into insulating it. Other problems include an occasional readjustment that is necessary on the light shroud to keep it from "sagging" in cold weather or when it is moist out.. this can be fixed as well according to Mag1 Instruments by using certain water repellent sprays.
Planetary performance is exceptional, and wide field views the same, with true pinpoint stars. M81 and M82 looked particularly nice and contrasty in my suburban semi-light polluted skies. M42 takes on the familiar powerful greenish appearance, with all 6 stars in the Trapezium easily noted. Saturn's "Encke minima" (50% out in the A ring, not the true Encke gap) could be detected, along of course with the Cassini division all the way around the rings, and the C ring easily seen. On Jupiter, there is a wealth of detail, with contrast lessening a bit after 300x as expected, but crisp, high resolution maintained right through 400x and beyond. *NOTE - I had this scope equipped with a slightly smaller than usual secondary to try to eek out even better planetary detail, probably has little effect*
A minor disadvantage to the scope is that you need two hands to carry it, and it's base from location to location. Also, the ten minute set-up time is not as convenient as a scope like the Teleport (pricey) which can be set up in less than 5 minutes. Lastly, and I find this an advantage, you need to sit down to use it, unless you are under maybe 12 years old. I prefer sitting and observing to standing and observing, I gain more detail that way.
Usually this scope comes equipped with a 1.25" focuser. I do prefer 2" eyepieces over 20mm, and the 22 Nagler works well in the scope, but does tend to make it top heavy when pointing close ot the horizon up to around 25 degrees. If you have your 8" custom made with a 2" focuser, keep in mind you won't realistically be able to use a 31mm Nagler, or 35mm Panoptic, or 20mm Nagler, or any other very heavy eyepiece.
11/19 Update: Had a chance to compare this scope to the venerable TSC225mm SCT from Takahashi. This scope did outperform the 225 visually, although it was close. More contrast and discernibility on most objects including the Trapezium in Orion. Planetary was close, and the cleaner view from no diffraction spikes in the Takahashi (lack of secondary spider) may make the view seem more pleasing to many users, but on actual planetary features, the jury is still out, but it may go to the Portaball. A very comparable match between two scopes with superb optics.
PROS and CONS: See 12.5" portaball
52.
Takahashi FS60-C f/5.9: Takahashi has produced the cutest scope
in existence with the FS60C. Only 14" long, maybe 2 lbs in weight, this
is a far cry from the much longer FC-60. The focal length is only 355mm
making this scope unique in it's color-free wide field views, and excellent
wide-field ccd potential . Color free? Well, sort of. The f/5.9 takes away
some of the advantage of the FC-60, so that even though the scope doesn't
show much if any false color on planets, and the moon, (in contrast to
the Televue Ranger which does) it still shows some color in the star test
inside and outside of focus. The Cassini division was noted easily on Saturn,
and the equatorial band was seen on Jupiter. (the festoonal band). The
scope has the standard dream Takahashi focuser, 1.25", smooth as silk.
It comes with a removable extention tube so you can use it with a 1.25"
diagonal, or straight through. The scope is particularly well suited for
CCD photography. If you team it up with an ST7 for instance, you should
be able to just about fit both M81 and M82 in the same photograph without
needing to use a mosaic. Lord knows what you would be able to achieve with
the ST8. While I hate to give away my ccd secrets, using a 355mm focal
length will enable you to go unguided on most mounts. Convential photography
must be outstanding as well, and needless to say much wider in field size.
Here
is a pic through this scope.
PROS: Tiny scope that performs and
is "fast". CONS: Some slight "color"
53.
Celestron Fluorite 70mm f/8 Fluorite: Here we go again with an
unbelievable Celestron Fluorite from years past. Only 21" long, black baked-on
type finish. 2" focuser. An "okay", not-smooth-as-takahashi focuser that
I wish was better. Something more solid about this tube than my previous
55mm and 90mm units. Color free performance, 560mm focal length. Scope
is once again performing above what I would expect for it's aperture. On
Saturn, the Cassini division was seen to circle the planet. Great resolution
on Jupiter's great red spot, and it's central festoonally induced belt.
Star testing not far from 1/8 wave. Weighs maybe 4 lbs or so. Lightweight
, yet heavy duty feel to the tube. Overall , a vast improvement over the
Televue Pronto at a similar 'resale-on-the-net' price. A rare gem. Here
are some pics with the scope.
PROS: Fabulous scope for deep sky and
planets CONS: Takahashi construction is better, and an FS-78 will
outperform this.
54. Takahashi TSC-225mm SCT f/12: Okay, I've managed to obtain one of these unbelieveable scopes. Only 100-200 were ever made, and documentation states they were all made to 1/8 wave or better (p-v). (seems about 1/7 or 1/8 wave to me) The best SCT ever made perhaps. My first views through this scope are very encouraging, but my original question remains unanswered.. Is it really worth nearly 3X as much as an excellent Celestron 9.25" SCT tube? (I have an unsually good C9.25" , Japanese "white" version that absolutely trounces other SCTs I have owned at the same time) Similar in size to the Celestron 9.25" , it weighs only 20 lbs. Smooth focuser with minor focus shift, a bit more than my C9.25" . Not as much in-travel as the Celestron. This scope has a smaller 28% central obstruction, and can be cooled more easily with it's venting holes, or if you can get hold of a computer-fan, or the fan that originally came with these scopes. Does not use standard visual back, so you need to get a specially made reducer from third parties if you want to reduce this to f/7. (essential a Meade or Celestron f/6.3 reducer that can "pop into" the 2" opening at the rear) The scope may have trouble reaching focus with a 2" diagonal when using the reducer, but it should work for CCD photography no problem. I have the scope mounted, like the C9.25" with a standard Losmandy G-11 bracket. The scope comes with an optional matching dewshield, nicely made, but not 100% effective on the worst nights.
After cooling the scope down
for quite some time, the star test stabilized and indeed it is approaching
the 1/8 wave as advertised, a tad better than my (excellent) C9.25". There
does seem to be a bit more contrast on the planets. I'm also seeing some
excellent performance on deep sky. The E& F stars of the trapezium
did not pop out quite as clearly as in the 8" portaball with Zambuto optics,
but they were still intense, and obvious. Excellent resolution on the planets,
and color saturation, contrast very good planet to sky, so that you can
move the planet out of the field, and go to dark sky with minimal light
scatter. Planetary views were "more pleasing" than the 8" reflector
(portaball) due to the lack of spider induced diffraction spikes. NGC2371
popped out very clearly from the black background sky, as did M76. M42
was Green, as I had hoped (good contrast) , M103 was extremely colorful.
PROS: Great performance
CONS: High power only. Price. Cool down time.
55. Takahashi FSQ106
f/5 - Ultra-Preliminary look (just got it)
The new Takahashi
is hard to review, because of my own pre-conceptions. While I am awaiting
tube rings to mount the scope, so far, I have only had a few peeks through
the scope. However, I am aware from my astro-friends of it's unbelievable
reputation not only for photography (quadruplet, 530mm fl, f/5, 4"
focuser) , but for visual work. It apparently is one of the best 4"planetary
scopes ever made, up there or even better than the revered FCT-100. Using
the optional f/8 extender, matched perfectly just for the scope, planetary
views are reportedly astounding, seemingly closer to 5" apo performance.
The key seems to be in the contrast of this 4 element scope. I can confirm
that when I moved the moon out of the field of view, the field went black...
there was no indication that the moon resided near the field of view, a
good sign. That said, I've had problems with the way Takahashi made this
scope from day 1. The main problem is back-focus. They made the tube too
long again. While it reaches focus at f/5 with almost all eyepieces, it
does so just barely. There is a special $300 diagonal that one can buy
from Texas Nautical to allow for 2" eyepieces, which is almost overkill
in an f/5 scope anyway.. but I can' see how it would work with the f/8
"extender". (note.. the 2" diagonal is probably necessary to properly use
a Televue binoviewer with 2x) The main limit is that one cannot use a "flip
mirror" for ccd astrophotography, and it would be harder to use binoviewers
as mentioned.
The scope is also just *barely* airline portable. While you can take off the dewshield, and bring the length down to 21" , as it stands.. the scope is 26 to 27" long. It should, if one buys a special carrying bag, (such as sold by Anacortes) work as carryon luggage. It is also heavy though, around 12-13 lbs. or so. It takes standard 114mm rings or the takahashi tube holder for their other 4" scopes. What is nice about the scope is the way it is so solidly built, the large dewshield, the incredibly smooth 4" focuser, the camera angle adjuster built-in (nifty takahashi item becoming more and more available) and the 1.25" compression-ring eyepiece/diagonal holder. It's put together REALLY well.
12/16/99 Update: After careful inspection of the star test in this particular scope, I discovered what appeared to be astigmatism despite excellent deep sky and planetary performance. I have sent the scope back to be checked out. I have made inquiries, and so far have found, among at least 1/2 dozen scopes, nobody else experienced this problem, so it's probably a fluke.
1/27/00 Update: I received a second sample and found an error that seems to be something like "pinched optics" only when the temperature is below 20 f. I was able to study the contrast that the scope offered, and indeed, it was hard to tell when the planets are just out of the field of view. (that' s great) Star test otherwise was not perfect, but close.. probably close to 1/7 or 1/8 wave, but in a complex scope like this it's not wise to try to quantify spherical aberration. Decided to postpone testing this scope until someone else reports this error so that Takahashi can address it. Moving on to another scope, the CN212 coming soon.
PROS: Fast scope, excellent contrast and performance. Very small for a 4" , even airline portable (overhead) CONS: Hard to get collimated if needed. Bit heavy for size. Takahashi "ring" is heavy, the A/P Traveler rings make more sense for a cope this size.
56. Takahashi CN212
Classical Cassegrain and Newtonian:
This is one fabulous scope.
With the best star test of any moderate or larger size compound scope that
I have tested, it will likely be a killer planetary telescope. However,
the planets are not available to me at the current time, so I will do a
lunar test shortly. Let's talk about this scope. It is 33" long, 18 lbs,
and rides nicely on my A/P 600 GTO mount. This is a convertible scope that
can run as a f/3.9 Newtonian (which isn't so great) and a f/12 Classical
Cassegrain (which is fabulous).The Cassegrain is like an SCT without a
corrector plate. This means less problems with dew, and potentially more
efficient light throughput than an SCT. It also means a bit less cool-down
time. Cleaning the primary mirror though, which is exposed, will be a big
challenge.
All that is required to switch from one mode to the other is a swap of the diagonal which unbolts so easily that the switch can be made in just about a minute. Focusing is achieved solely by moving the main mirror in both modes. Collimating tools are included, but once collimated, the secondary mirrors do not lose their collimation during the swap. The collimation of the Cassegrain diagonal is straightforward and easy. I can't say the same about the Newtonian diagonal, and I can hardly comprehend the awful Takahashi instruction manual, which is written as usual in translated English that is barely readable.
To mount the scope I was able to mate the tube ring to a Losmandy dovetail plate (G-11 type) by matching the screw holes to the DUP plate. A finder that can be illuminated is included with the scope, although the illuminator is optional, I had to put in my own. While the focus position was fine in the Classical Cassegrain mode, one needs an extention tube for proper focus of most eyepieces in the Newtonian mode. (still checking into this with the supplied Takahashi field - flattener which may help) I prefer it this way to the other extreme, but the oversized diagonal could have been smaller if Takahashi had thought this out more, and pulled focus in. Fortunately the tube ring is easily loosened to allow one to rotate the tube, helping to view in Newtonian mode, as a Newt. is hard to view through on an equatorial mount.
I'll talk about the Newtonian views only briefly. At f/3.9 (800mm f/l) the field of view is huge in a low power eyepiece. Astrophotography (ccd and conventional) will benefit from the fast focal ratio. The supplied Takahashi field flattener works only with photography, and to reach focus correctly for visual use, you need to use the supplied takahashi 1.25" adapter. While you can get 2" eyepieces to focus without the 1.25" adapter by utilizing extention tubes, you really do not need 2" eyepieces usually anyway with such a "fast" scope... so I would recommend using adapter as supplied. The wide field of view is beautiful, the star-test very good (but not nearly as good as in Classical Cassegrain mode). However, the really noticeable "sharp" performance was in Classical Cass. mode. Nevertheless, M13 and M51 looked almost as good through the Newtonian mode as in Classical Cassegrain. Extensive galaxy M101 was particularly impressive at low power, which is viewed best in this kind of fast scope and wide field and wide exit pupil. I did take a ccd photo through the Newt mode of M92.
I had the CN212 in Classical Cassegrain mode up against my 10" Teleport with Zambuto optics (generally unbeatable) . The fairly thick spider veins on the CN212 make for larger diffraction spikes than the Teleport, and in fact, it may distract you if you are used to the lack of any diffraction spikes completely in SCTs. (This scope has no corrector plate, so needs the spider) The spikes are only really noticeable on very bright objects, as in any Newtonian. Despite this, and a 32% obstruction (better than most SCTs) this is a high contrast, very high - resolution view. Other than the diffraction spikes, one cannot tell when a bright star is just outside the field of view. Stars are extremely sharp, and the field quite dark. M13 is beautifully resolved and very close to the view of the 10". M51 barely shows the spiral dark lanes, but does clearly show the approximately 14th magnitude foreground star. After allowing the scope to cool for quite some time, the star test eventually became unbelievably good for a compound scope. Undercorrected while cooling, but eventually 1/8th wave or better at the eyepiece, with the central obstruction "breakout" even on either side of focus, unlike in Newtonian mode. Focusing is VERY smooth... the main mirror is moved for focusing both in Cassegrain and Newt. modes. However, my unit does have a slight "focus shift" as is typical in this kind of system, but worse than I expected from a $4,000.00+ scope. Focus leeway was okay, but not as generous as in a typical Celestron or especially Meade SCT. Thus, a binoviewer could NOT be used with this scope without a barlow (won't reach focus).
3/8 Update: Checked scope out directly against the C9.25" . The C9.25" does gather more light, and it can be seen with 14th magnitude stars showing up more easily. Contrast seems higher on the CN212, with slightly more pleasing views of M51 and M101. Lunar test coming down the road...
3/21 Update: Lunar test is very encouraging in Classical mode. I've leaned not to like the Newtonian mode just because I don't like Newts on GEM mounts with the eyepiece way up top. In classical cass. mode I'm showing in mediocre seeing conditions a lot of detail on the moon, a good 5 or more craterlets in Plato--many more to be discerned when seeing steadies, I can tell by the sharpness of the microfeatures. More later..
The CN212 is available from any Takahashi dealer. (Traded for it through GCS, also talked with Anacortes, and also available through Texas Nautical)
PROS: Sharp optics! Ultra-versatile, easy to swap diagonal CONS: Hard to collimate
57. The William
Yang 100mm F/8 Fluorostar (TMB designed): (2000) Updated 3/21/00
Beauty is the only way to
describe this scope. Beautiful hardware, beautiful star test, beautiful
images. The pearly white glossy finish of the scope is highlighted
by gold trim. I received the scope from Anacortes Telescope and Wild Bird.
The scope weighs about 14 lbs and breaks down to 24 1/8" long, and is just barely airline portable. (Overhead should be okay in a 25 or 26" long soft case, such as the 26" Tenba which it fits perfectly in.) It can break down even further if you unscrew the built-in camera angle adjuster. The hard supplied case is around 8x12x27, possibly acceptable as airline portable. Supplies include a matching finder bracket, the included camera angle adjuster (like Takahashi supplies optionally on their scopes), a rotating 4" focuser (so that you can position the finder in a different location) & two caps, one for the objective, and one for the sliding dewshield. Also included is a 2-1.25" adapter. (The hole in the focuser is made for a 2" diagonal.) Also included is an extention tube which is rather unique. The extention tube is effectively a part of the scope that is taken out, and really needs to be screwed in or you won't be able to reach focus even with a 2" star diagonal. This sounds like a disadvantage, but it is quite the opposite. This allows the f/8 scope to break down for airline portability, unlike the f/8 Takahashi models. (The huge sliding dewshield helps here too) In addition, if you unscrew the 3" extention, and use a 1.25" diagonal, you can actually reach focus with a Televue binoviewer WITHOUT using a barlow, since the tube is "too" short. This is the only refractor other than the Televue Bizarro that I know of that can do this. On the other hand, if you want to use this scope for photography straight-through, or view straight through..without a star diagonal, you are going to need another extention tube to reach focus, not supplied. The 4" focuser is beefy and nice. The focuser tension must be adjusted fairly tightly though to avoid the draw tube from slipping. This same tension knob when loosened allows you to rotate the whole focuser to position the finder bracket more conveniently. However, this is not a smooth rotation like that of the camera angle adjuster, which allows you to position your camera, ccd, or diagonal easily any way you wish.
The star test is unbelievably good.. Supplied documentation shows 1/5 wave p-v, and 1/45th wave RMS, and a .98.2 Strehl, yet, the star test shows up at the eyepiece as way better than 1/5th fer sure (as of 5/1/2000 I have checked it many times and can confirm, when cool, it's just about perfect). There is NO false color, none. I didn't even realize the A/P Traveler had any color in the star test until I put this side by side with it, then I saw it. The snap-to-focus is sharper than anything I can recall. M13 resolves easily. M51 and M101 were particularly beautiful, so was M35, NGC5005, NGC5033, M94, M63 (wow!), M10, M5, M92. The 13th mag. star shows up easily near the Ring Nebula, no hint of the 14th mag. star next to that one. Seeing has been poor.. but I can confirm that the central belt on Jupiter that all the festoons flow to was visible, and bluish. Lunar performance is outstanding with many craterlets in Plato counted, at least 4. Izar split easily anyway with an unusually strong blue hue to the B component, and at times it completely overwhelmed the weak "first diffraction ring" indicating a good optic. Contrast was great on M42 in the 27mm panoptic, and stars were pinpoint to the edge. The scope works very well with a 40mm Pentax XL too. First ccd image with this scope under partly cloudy skies, so some noise in the image, still good. I'm eager to put this scope up against the Traveler down the road. My initial reaction is that the views are very similar to the A/P Traveler and the Takahashi FS102, with perhaps more contrast. I have been told that the planetary performance on this f/8 model will excel. (Below I compared this scope to the A/P Traveler, read on..)
One note: There is some confusion as to where this scope stands in relation to the available TMB (expert optical design Thomas Back) scopes. See Ed Tings page http://www.scopereviews.com for a review of the former TMB scope that is the twin of this one, but this is the latest generation with some improvements aimed at bettering the contrast. Apparently the Yang scopes are still of TMB design, however, Thomas Back is selling his designed scopes in other tubes as well beginning now in the year 2000. Markus Ludes is also selling TMB designed scopes. Sooooo, yes this is TMB designed, but it is officially a "YANG".
05/04/00 Update: I just spent two nights straight comparing to the f/6 A/P Traveler VERY carefully matching diagonals, eyepieces, focal length, etc. There is no question that the Traveler has a very slight edge on deep sky in terms of star detection (due to the 5mm additional aperture I suppose, adding 10% to the light gathering over the Yang) This includes slightly more resolution to M13. However, the contrast seems to be a microtad better (on deep sky in suburban skies) in the Yang, and thus certain objects seem to stand out slightly better, including M101, M57, and M27. I will compare again late summer on planets, where I am told this scope may have the edge, we will see.... (by the way, BOTH scopes split the double-double very widely and cleanly) 5/9/00.. I had a chance to compare on the moon, and both scopes were virtually identical in performance in fair seeing conditions (turbulence)
6/14/00 Update: Another comparison against a different A/P Traveler turned out as good, if not better performance (seemingly a bit sharper, with a tad more contrast offset the 5mm difference) A night of splitting doubles was fun, 1.2, 1.3 arc second separations were easy at only 200x. I noticed a slight collimation problem when splitting them on a perfectly still night and have sent it back for collimation. This is great scope, one of the best 4" ever made.
PROS: Great optics. Great
construction. Abundant focus travel CONS: May be hard to get serviced.
Too large for easy airline transport (it's close at f/8)
58. TAKAHASHI FCT-76:
Okay, this scope is just
too perfect. I already love the Takahashi tubes in general. From the smooth
focuser, to the green highlights, I tingle when I have one on hand. To
actually receive a 76mm Takahashi that isn't too long, was a thrill. With
blue and red highlights, the tube is only 17" long when you unscrew the
adapters on the eyepiece end... and the dewshield is shorter than normal.
(may produce a problem when heavy dew is forming, but otherwise helps for
airline portability) It weighs just a few pounds. Perfect for airline
travel. The FCT76 was recently discontinued again from Takahashi, and second
hand prices have crept up over 2,000, this is not a cheap 3" scope.
The performance of this unit
is mind boggling for it's size. The star test was very slightly undercorrected.
I had heard that there were some occasional optical problems with the FCT
series, despite their excellent (unrivaled) reputation, but did not find
this at all. The scope is a triplet, and there was no false color detected
on any star or object at all. It's a pure APO. I bought it with the "Texas-Nautical
Repair" supplied 2" adapter, which screws onto the scope to allow a full
range of focus travel for both 2" and 1.25" eyepieces. I was surprised
how well it worked, as normally this scope has minimal focus range (3/4"),
and is it's well-known weak point. (although I used a very shallow 2-1.25"
adapter in order to reach focus in the 2" diagonal with certain eyepieces,
there was no eyepiece I could not get to focus!) The views? Unreal. M13
actually resolved to pinpoint stars, under the same conditions as the Televue
85mm, it resolved about the same. (Pinpoint stars noted, but not everywhere
all at once, although more resolution on both scopes was recently obtained
in a side by side test - see below) What really shocked me was M57. I was
sure I would NOT be able to detect the 13th
magnitude star near M57, since I only "suspected" it's location in
the TV85, in excellent conditions. (later firmly detected, see below) However,
there it was, plain as day with averted vision, about as easy to detect
as in the A/P Stowaway (92.5mm).
4/00
Update: COMPARISON of the Televue 85mm to the Takahashi FCT76.
PROS: Best scope in this size category. Airline portable (overhead) CONS: Sky90 from Takahashi can out-do it at same relative size (of tube) and price
59. Meade 10" F/6.3
SCT Tube Only:
Just received this scope.
It had been damaged in shipping and rebuilt by Meade. Optics are very good,
about 1/4 wave, initially appeared to be better, night-time "cool-off"
may have offset a 1/4 wave of overcorrection (usually they seem to be undercorrected,
so this was interesting) Still testing, initial views are very pleasing,
similar to C9.25".
6/14/00 Update... In a back to back with the C9.25" I found the Celestron to be sharper. Cleaner split on the close doubles with ample cool off for both scopes. Both scopes were well collimated. I'm not sure if it is the obstruction, the slightly better correction on the C9.25" or just the overall optics. Generally I have been more impressed with Celestron than Meade. It's still a fine view with great resolution on globulars, and plenty of light gathering, giving similar views to the C9.25", but my special "Japanese" white version of the C9.25" came through and beat this scope.
This scope also provided
fine CCD performance. Using the reducer, I was able to reach focus with
a flip mirror to reach f/4 with no problem, and frankly, the pictures came
out great.
PROS: Price CONS: Celestron may
be more consistent
60. Williams Optics
("Yang") 105mm f/6.2 APO?
There was a mix-up with
this scope, as it may have been a 102mm, optical origin unknown. The optics
were nice, except for a zonal error in the middle which was intentionally
designed to reduce "spherochromatism". I am not clear on the details, and
thus am moving to the next scope until I hear more from the dealer as to
what size and focal ratio scope will be available on the market.
I may revisit this later this year, as the potential is there for a great
scope when details are worked out, and the scopes re-released. Meanwhile,
the F/8, still available in the US is of course, superb, and listed above.
PROS: Small enough for
easy airline (overhead) transport. Abundant focus travel. Great optics.
Great construction CONS: Bit hard to get serviced?
61.Takahashi FSQ106N,
106mm f/5)
Call me obsessed, but the
sliding dewshield on the new "N" version of the Takahashi FSQ106 has moved
me from "lukewar" to "excited" about the mechanics of this scope. Like
the FSQ106 regular version, it still has too little focus in-travel, but
optically this time I received a winner.
The contrast on the moon is absolutely incredible. Cirrus clouds swept by the moon and were illuminated by the moon in front of the black sky at high power, it was awesome. I had the A/P Traveler right next to it, and found just a "tad" less contrast moon-sky in the Traveler, but it was close. I needed to take out all star diagonals to maximize both scopes. The Traveler (refigured June, 1999) and it's excellent optics were not out-done by the FSQ, but it was virtually a tie. Same amount of star detection, nebula detection, and ability to take on high magnification (very crisp through 300X on both in medium "seeing conditions") I did notice that the takahashi had the best overall "snap-to-focus" of any scope I've tried...probably partially due to being f/5. At f/5, it's tough to evaluate the star test, but any aberrations are low.
I have figured out a way to reduce in-travel using a Feldstein adapter (got it from Anacortes Telescope) so that I can use a small flip mirror with my ccd. However, one still requires a special 2" diagonal which is scope-specific for 2" eyepieces if you want to use one. With an exit pupil of 5mm with a 25mm eyepiece, it is questionable if you should go out and purchase the 2" diagonal. If I keep the scope I will do that.
The sliding dewshield brings
the scope down to around 21" or 22" , but if you unscrew the back plates
and eyepiece holder (not recommended because it exposes the rear element)
you can just barely fit this in a Traveler bag. (It's a tad too fat for
the bag, & a tad too long) That makes this ultra-airline portable like
the A/P Traveler. However, fitting it into a 22" Tenba case would be wiser,
and I think you can leave on the back (eyepiece holder and plates). This
is the first scope that really can take on the role of the Traveler, but
you also need to consider how you are going to mount the tube. The Traveler
has built-on thin tube rings, while this requires the standard 4" Tak.
"ring" which can be cumbersome depending on how you mount it. Nevertheless
at f/5, this is a joy to use for CCD photography, and both high power and
rich field viewing. One of the more exciting scopes to hit the market in
the past few years.
PROS & CONS: Same as FSQ106 with
even more portability
62. The Televue
102mm
Apo
The Nagler's have done it
again with the Tele Vue 102. The Tele Vue-102 is a 4-inch (102mm), 2-element
f/8.6 APO air-spaced doublet, similar in size and appearance to the 4-element
f/5.4 Tele Vue-101. The maximum field size is still jumbo (despite being
a slower scope than the TV101) at over 3 degrees. Like all refractors without
a rear lens group (as built into the Tele Vue-101, and Takahashi FSQ106)
a field flattener is needed for conventional photography of star fields.
However, according to Televue and
Anacortes
Telescope and Wild Bird, a dedicated 0.8x reducer/flattener will be
available, to permit astrophotography at f/6.9 with the Tele Vue-102.
Unlike most other TeleVue scopes, this one is offered "a la carte". No diagonal, no tube ring, much like you would buy a Takahashi tube. This brings the price pretty close to the 2,000 level which is quite a bargain when you compare it to the street price of other high-end apos. If you are like me you already have a diagonal, and may have tube rings to fit. The scope is around 33" long and does include a hard plastic case, sturdy and well built. The scope is very light, under 10 lbs, and a pleasure to handle.
Anacortes contacted me and asked if I would like to review the scope. I chose randomly from 6 serial numbers, and the scope I picked arrived 3 days later. I tested this scope the first clear night right next to other high-end apos. I was curious about the scope because I also own and love a Televue 85mm apo. The TV85, at f/7, is able to achieve apochromatic performance with only the most minor of false color noted. However, raising the aperture to 102mm surely would increase the amount of "color" unless the focal ratio is lifted as well. Apparently that is just what TeleVue had done. The scope with it's f/8.6 focal ratio has done the trick. The star test showed very little color in or even out of focus, if anything less than the TV85. No color on Vega except at highest magnifications. None on the moon.
The startest itself was excellent. Perfectly round diffraction pattern almost identical on either side of focus. I also tested with color filters. It seemed to be about 1/8th wave at the eyepiece. (undercorrected) The scope was perfectly collimated as well, with no optical errors of any kind.
The first object I turned to immediately impressed me. Here we were, just past full moon, and M13 was beautifully resolved to strings of individual stars. Resolution was as good as the A/P Traveler and FSQ106 I had nearby. (I matched magnification) Same thing on M57, the 13th magnitude star nearby the Ring Nebula was barely visible in all three scopes. (photometry confirmed by Brian Skiff). The contrast near the nearly full moon was excellent, with a black sky surrounding it. The FSQ106 had the best sky-moon contrast when moving the moon out of the field of view, however. The moon was crisp through the 292x magnification I put to the scope. The most impressive object was Epsilon Lyra, the double-double. The scope was actually able to split it only 62X (14mm radian). At 292x, and 220x the split was wide and clean, with only the faintest first diffraction ring showing around the four stars. Seeing conditions were coming and going, and the focus held for longer periods of time with this scope, than the other two apos, making the double double look best through the TeleVue 102.
Mechanically the scope is a joy to use. The two inch focuser is buttery smooth, and identical to the focuser on my TV85. Mine came with an ivory tube, and a nice long dewshield. My only criticism of the dewshield is that you have to retract it in order to put on the endcap.
$2,050.00 for one of the best apos on the market is a great deal any way you look at it. The only suggestion I could make for the scope from a logistical standpoint, is to make it airline portable. Perhaps there could be a way to safely engineer a tube that can be broken down. The scope is so lightweight, it is a shame that the nearly 3 foot length makes it tricky to bring onboard as carry-on luggage.
This scope is gong to Ed Ting next for review (www.scopereviews.com) and then back to Anacortes where it will be sold as an open box demo. Lucky is the buyer that gets this scope at below market due to the testing. Now if only we can convince Televue to come out with a similar scope but with even larger aperture...... Say "hi" to Al from me when you make that request :)
PROS: Superb optically CONS: Too long for overhead transport
63. The Pentax 75mm
f/6.7 SDHF- Available from Markus
Ludes the Pentax 75 is an intriguing in-between in mechanical quality
from the Vixen line to the Takahashi line. In a not-as-attractive-as-Takahashi
green tube, The Pentax is very small, only 15.75" long when fitted with
a 2" adapter that was included with my demo unit. It's also only FOUR pounds.
(Make sure you get the appropriate adapters to allow you to use a 2" or
1.25" diagonal etc, it's focuser opening is a non-standard size) The focus
position was pretty far "in", and I needed a shallow 1.25" adapter to reach
focus with some eyepieces rather than a standard one. While I don't do
conventional photography, the larger focuser size surely must be an improvement
than the standard 2" in the TV85 if you can mate your camera properly.
(Pentax adapters are available)
The instruction manual is
in Japanese. The scope is a doublet with an integral field flattener, far
down the tube. The scope has a sliding dewshield, but you can leave the
front cover on as you slide it in and out which is convenient. The front
end cover also, like many Vixen and Takahashi covers, has a hole that you
can open in the middle (for solar (with smaller filter) or lunar observation?)
The tube comes with a takahashi-like tube ring that is much lighter, and
easily fit on my Televue Telepod. It balances well. There is a 1/4-20 hole
in the bottom so you can attach it to a std. tripod. One nice feature,
the end of the tube is rubberized,so that if it flops over, it just bounces
off the telepod, rather than risking any minor damage.The focuser is not
that great, but works, it just feels cheap. The focuser locking knob is
a lever on the right hand side, similar to TMB scopes and easy to use.
While I did not have the FC76, FCT76, or FS78 handy, I had previously tested the FCT76 against the Televue 85 (Bizarro) which I did have on hand. The star test was excellent, a small aberration noted coming just out of focus in the middle. I previously estimated 1/7th wave spherical aberration, then felt I was a bit too optimistic. Then, Markus corrected me and said it's tested at 1/6th (Markus is conservative in general when quoting correction, so that's a very good number) Views were wonderful. Some very minor color was noted on Vega and a few other stars, but quizzically, the color did not seem to worsen at high power as it does in other scopes. (About the same amount of false color as in the TV85, very slight.) I took it through 335X. By day, there was noticeably more contrast than the TV85. By night, the TV85 had the edge with the greater aperture. Unlike the FCT76 which seemed a little dimmer than the TV85, but could pick up any star that the TV85 did, the Pentax 75mm fell just short in that regard, unable to detect certain threshold stars that the TV85 could achieve. This meant resolving M13 barely, but not really being able to appreciate the shape, and the strings of stars, like you could in the TV85, or even the FCT76 for that matter. M51 looked just about as good as in the 85mm though. M52 was also very enjoyable. Izar split better on one night in the Pentax, the next night in the TV85. The double-double in Lyra split at just about 50X in both scope, perhaps slightly better in the Pentax (possible due to the tad less light gathering more than anything else) The scope holds high magnification extremely well, with a classic airy disk and diffraction ring, when seeing allows. Taking the double stars to 335x was no problem at all, despite only 3" aperture!
Scope has been given to Ed Ting who has posted his evaluation of the scope
PROS: Great performing small,
easy (airline overhead) to transport scope. CONS: Not as pretty or built
as well as Takahashi scopes which can outperform this.
64. Takahashi
FS152 - (7/2000)
Depending on how you look
at it, the FS152 may just be the best all around telescope in the mid-size
range (mid size meaning 5 to 7" refractor, 6 to 12" reflector/compound)
The scope is sharp when using a low power eyepiece for a large 2 degree
field of view, and yet it easily can be pushed to 300 and 400X with available
eyepieces and no barlow for some of the best planetary views available
in a wide range of conditions. It also has the right focal length for most
"CCD objects". In addition, I found that this 6" refractor f/8, f.l. 1216mm,
takes the word "pinpoint" to new levels!
Initial notes: Star
test very good. Some (false) color is definitely noted on bright stars
at high power. Comet Linear extremely beautiful and contrasty. Have glimpsed
a 14.6 mag. star near M57 with averted vision. Split .9 separated double
at around 400x. Star test is good, much like all the other larger TAKs.
Scope is very lightweight, but long, around 55".. can't believe it's even
the listed 24 lbs. A/P 600eGTO mount handles scope adequately. A bit less
stable when pointed in certain directions .
Further evaluation:
The scope is performing better than any other I have owned for it's size.
In other words, it is seemingly "beating the seeing" conditions and producing
super-sharp detail on the moon and planets more regularly than other scopes
I am putting it up against both smaller and larger. This can be attributable
to fine optics, and of course the lack of a central obstruction like all
refractors. The scope shows detail head and shoulders above 4" refractors
such as the A/P 101 and A/P Traveler. While the 9.25" SCT (excellent) does
show similar detail in moments, the 6" TAK is holding the sharp image better
in a variety of seeing conditions (turbulence) While it is conceivable
that the 9.25" will out-do it in a time of super-steady skies, I have not
experience that as of yet. M31, and detailed evaluation of M32 and M110
shows high contrast deep sky viewing. M13 resolves easily and completely
to strings of stars with no problem. The question is does this scope perform
better than the A/P 155 triplet, or even it's own cousin the Takahashi
FCT-100 (triplet) From my memory, the detail is greater on Jupiter and
Saturn more regularly than in the A/P 155, but that is without the scope
at my side to compare it to, so I am giving the scope to Ed
Ting to further evaluate as he currently has a 155 available to test
against. (His results give the A/P a slight edge.. but the TAK a contrast
advantage)
The one problem with the scope is some minor false color noted on bright stars and Jupiter both in the star-test and in-focus.. . but it's hardly noticeable on either the moon or planets. It's very subtle and hard to detect. By the way, there isn't one night that I have not been able to make out the Cassini division ALL THE WAY around Saturn's globe, not just off on it's sides. The Encke minima is almost always available too.
Last test was against a 14.5"
Starmaster/Zambuto stopped down to 6". The takahashi had similar resolution,
but much better color saturation. Planetary images from fabulous session
on 8/30/00 can be found
here.
PROS: Unbelievable performance full
range from deep sky to planetary CONS: Slight color
65. Televue
101, 101mm f/5.4
This marvelous refractor
looks and works (mechanically) like the Televue 102 already reviewed, except
it has two extra elements which act as a field flattener and reducer to
f/5.4. Thus, this is one heck of a great CCD and photography scope, yet,
it doesn't suffer by being even faster than the A/P Traveler. I had this
and the Traveler up against each other several nights running and they
were just too similar to draw a conclusion as to which was better. This
was interesting, and confirms the Televue claim that their unconventional
baffling system indeed works, and works well. I did note some slight "color"
in the star test, but it did not show up in-focus. There was also a very,
very slight edge on star detection and globular resolution in the Traveler,
I think because of the extra 4mm, but it was very, very slight. Jupiter
and Saturnian views were remarkably similar along with lunar views at all
magnifications. The one failing of this scope of course is that it is not
airline portable. However, it is a heck of a 4" refractor that performs
along with the very best. By the way, as expected, he star-test is quite
good.
PROS: Fast, corrected
scope for photography CONS: See TV102 above
66. DGM 4" Off-Axis Newtonian Dob - I have handed this review over to Ed Ting
67 14.5" Starmaster Truss Dob/EL Hybrid - Amazing "do everything" scope. Sized just right for on-feet, no-ladder performance for most users (5'7" and over) I ordered this with the GOTO drive system, which somehow seems to work a bit better than on my previous 18". All objects fall within eyepieces of around 15mm-20mm. The scope slews silently and effortlessly, and quickly object to object. After a very slight drift, objects stay pretty much dead center in the eyepiece for quite some time. Setup is easy with the Sky Commander system which does the "thinking". The scope can also be operated manually if one wishes, but unlocking
Unlike the larger sizes, the 14.5" is set up as an "EL-hybrid". In other words, like the smaller Starmasters, the whole thing can be disassembled easily into three parts, the top including the truss poles and upper tube assembly, and the rocker box and base. I already had occasion to transport it, and breakdown, setup and recollimation took very little time. Small enough time to actually make one WANT to travel with the scope rather than to dread it.
The star test on the scope is phenomenally good for large aperture. Although rated roughly the same as my previous 16 and 18" with Pegasus optics, something in the optical train is allowing me this time to actually see a nearly perfect star test at the eyepiece. I need more stable skies to confirm this.
The view is great with super-sharp planetary images, and high contrast on star clusters, galaxies, etc. M42 is the bright non-washed out looking green that I look for in better scopes, the Trapezium was easy in mediocre seeing & NGC891 shows off it's wonderful dark lane. However, the view is noticeably dimmer than in my previous 18". Not that much, but enough to notice the lack of certain foreground stars that I became accustomed to on M1, etc. In my darker suburban skies, I found the light pollution somewhat distracting on the 18" however at all but the higher magnifications, that isn't as much a problem with the 14.5", where I am comfortable all the way to up to around 25mm. In fact, with a Televue Parracorr, and a 22mm Panoptic, I find the light pollution minimally distracting.
I can't say enough about this Dob. Between the super, thinner, Zambuto mirror that cools down fast, the GOTO drive system, and now the quick breakdown, this is about as good as it come.
Oct 2001 update: Planetary performance is far better (consistently) than the finest 6" refractors
PROS: Unreal performance. Versatile transport configuration CONS: GOTO system nearly perfect but not quite
68. Takahashi
90mm f/5.6 FCL-90 "Sky90":
Nice to report that Takahashi
did not disappoint with this long-awaited offering. The Sky 90, is a superb
fast scope (f/5.6) with well figured optics. This tiny scope measures a
mere 13 3/8" when totally broken down, and it's retractable dewshield retracted.
It weighs about 6 lbs, but picks up a couple of pounds when used with the
Takahashi tube ring. It is built in the typical Takahashi quality
style and color, and is supplied with what I believe is a 2.7" focuser,
that I used with the 2" attachments for a standard 2" A/P star diagonal.
Without the diagonal, but with the 2" accepting back, it is 14 1/2" long.
The focuser is very smooth, and focus position is perfect, although like
most refractors there is not quite enough in-travel to use the A/P Binoviewer
unbarlowed (you can do this on some of the larger Tak models, and virtually
all the A/P models, and on some Yang and TMB models, and I understand with
the Extender-Q that the A/P binoviewer will work).
Optically, being a doublet there IS some color, as you would expect with a doublet at f/5.56. I checked out the color very carefully, and it looks more like classic "dispersion" in focus, rather than the purple haze of typical secondary color. Reading below, you will find out how I reduced the color to practically nill..... (I used various eyepieces for these tests)
Out of focus, most stars will show purple in the parfocal star test outside of focus. (purple inside the rings, purple outside the rings when inside of the focus point) However, in-focus, only brightest stars show some purple on one side, and red (and/or green) on the other. This is limited, but there. On Jupiter, when seeing conditions steadied, the color was hardly noticeable with a slight purple off of one limb, and a slight red and green off the other. Again, this was very slight, unless I used my glasses, in which case it was made much worse (odd, my glasses caused the aberration with this particular scope) Also, the minor color lessened with magnification rather than worsened. There appeared to me to be slightly more color than the Televue 85mm f/7, also claiming to be an "apo", but like the TV85, this color is minimal and will bother mainly those observers hell bent on a totally color free image. At times of poorer seeing, the color seems worse than the f/7 TV85, but when seeing is good, the little bit of color seems worse or at least the same, in the TV85.
However, after I wrote the above, I tried the Sky 90 with the Extender - Q. This pricey little item (like a barlow, increases the focal length of the scope and appears to be integral to the scopes optical system once you attach it to the back) I thought was meant for just the FSQ106, but indeed it works perfectly with this scope. Coma in the field was reduced to next to nothing, and some of the false color as described above was wiped out in-focus. With such a low power scope to begin with, I highly recommend the Extender Q for use with this scope. (I used it at something less than it's 1.6x standard magnification, by the way, by removing an additional portion of it's extention tube.)
Observational highlights included deep sky. I have to disagree with Ed Ting (http://www.scopereviews.com) about just one thing about this scope, I do see it as a deep sky scope, brighter nebula and especially clusters, and ESPECIALLY comets. M37 was absolutely wonderful with it's central star surrounded by it's sea of jewels. M35 was excellent too, with NGC2158 visible but not resolved nearby. The contrast was exceptionally good, but what shocked me the most was when I went hunting for M81 and M82. Hard to find due to a poorly oriented 1x pointing device at the time, I thought perhaps I missed them in the suburban skies. When I finally stumbled on them, they were great, extremely prominent..right through 167x, and only a .6 mm exit pupil! A central dark lane was easily detected on M82, and M81 showed off it's foreground star, and was almost as impressive as through much larger aperture. I can't wait to try to split M13 with this scope. I have received word from a user of this scope in Switzerland that he detected the dark lane in NGC 4565 in mag. 6.5 skies. (Since have split M13 well even in last quarter moon)
Doubles were split in so-so seeing through 1.6 arc seconds, but I haven't tried this yet with the Extender q, and I think the doubles will be more cleanly split with it, (just confirmed that on 1/12) since the airy disk adn diffraction pattern seem cleaner with that in place. (yup, since confirmed) Saturn easily showed off it's Cassini division. Jupiter showed a wealth of detail including the split in the SEB, the NTB, and NNTB. The disks of the Jovian moons were all differing sizes, which is achievable only with 80-90mm scopes and above (below that, only Ganymede looks larger, if that) Many craterlets were obvious in Plato on the Moon as it approached full. I guess my point here is that for the size of a 70mm Pronto, 80mm Brandon, or 80mm Megrez (William Optics), you get more powerful deep sky performance due to the extra 10mm, and yet because of the fast speed of the scope, and two inch focuser, you have the opportunity to go to a very wide field. Using a 35mm panoptic, which is about as wide as one should go on an f/5.6 scope, you would yield a good 4 and a half degrees worth of sky. Thus, very large nebula in dark country skies would be optimal with this scope, like the A/P Stowaway (92.5mm f/4.8) This would include cometary tails.
Additionally, the parfocal Sky 90 star test was excellent, slight undercorrection which we see in almost all TAKS. No sign of astigmatism, zones, and very even illumination through the rings, although more fuzzy outside of focus, crisper inside of focus as usual for almost all taks. (but not all of them).
The scope is easy to mount, on tripods or takahashi mounts. Using a Wimberly mount on top of a Gitzo tripod, I found the scope much easier to manipulate than an A/P traveler, that is comparing 90mm to 105mm. I would suggest that Takahashi get on the horn and come up with some tube rings similar in size and function to the A/P Stowaway (rare, 92.5mm scope) which is more built for airline travel in mind.
More to come...
2/15/01 update: I have received word from an optical expert that the scope will show typical atmospheric dispersion more easily than a fully corrected triplet, and that is the type of color I was seeing, not the classic "purple haze". This is aggravated by seeing conditions, meaning that when seeing allows for good planetary views, this effect will be minimal anyway. Additionally, I have received word from around the globe that while most users are thrilled with their Sky90, there have been many units that have fallen slightly out of collimation in shipping. Mine in fact was a tad out of collimation, noticeable only at high power in-focus, and Texas Nautical, as usual, quickly rectified that supplying a replacement unit which seems fine. Still checking. Very impressed with TNRs quick turnaround as they use DHL. Additional testing on Jupiter and M13 reveal absolutely superb performance.
7/12/01 Update: In a comparison test against an A/P Stowaway f/4.9, I can find no significant difference in performance when utilizing equal magnifications. However, I still need to fine-tune the collimation on the sky 90 even more and have found out it can be done by the user, according to an one Swiss amateur. Also, I really am finding the false-color to be almost non-existant in-focus on the Sky 90. There is sometimes some at times of poor seeing, and the Stowaway holds the upper hand, but it is close, at least visually. I have been told that the newer Sky 90s as of 8/01 will have a new collimation scheme that will hold much better avoiding the collimation problems I have run into. I hate to say it, but the Sky90 which is one of the best telescopes I have ever run into, even for the price, is plagued by this minor, but annoying lack of ability to hold its collimation. The only real objects that this is making for difficulty is in splitting close doubles, but as the collimation slips, it is bound to show up in other high power performance sooner or later.
PROS: Best performing 90mm?? (tied with A/P Stowaway and Vixen 90??) Can be fit with smaller ring from Texas Nautical to make it even easier to carry on airline (overhead) Out-does TV85 and FCT76 on planets. Very nearly 4" scope performance, in a 14" long scope. Uses standard FS78 and FCT76 accessories. CONS: Does not come with case. May be more susceptible to atmospheric color aberrations such as dispersion than a triplet when seeing isn't great. Has significant coma without the Extender Q on wide field eyepieces. Some units have collimation problems, something currently being addressed by Takahashi
69. Edmund Scientific
Astroscan 4.5" "ball" reflector f/5
This is a great starter scope to say the
least. While $300.00+ new, it is only $200 at most on the used market,
and is a steal at that price. Why? Because it not only surpasses the crop
of cheap refractors costing much the same, but it has it's own built-in
ball mount, is highly portable, perfect for children, does not require
a finder, and is very stable. Here is what you get with this unique scope.
1. The scope itself which is Newtonian similar in design to the Celestron "comet-catcher", but here designed solely for visual use, and thus it's "ball" mount. It has an optical glass window holding the diagonal, so that there will be no diffraction spikes. However, in use, the scope, like a "Portaball" is placed in a cradle and can be moved around the sky, as it sits table-top. I believe there is a low cost tripod adapter as well.
2. A bracket slides onto the scope near the eyepiece which acts as a "1x" finder. It is just two holes that one lines up by sight, but it works.
3. A strap.. this is the most unique part of the scope.. The scope can be strapped to you, with the shoulderstrap, so that you can pan around the sky manually while holding the scope.
The scope moves very well across the sky
with ease, although it wasn't as smooth as a Portaball which is a premium
design. It also didn't work as well when the pads in the cradle got wet
with frost or dew. The 1x pointer works fine. The 1.25" eyepiece holder
was set at the proper distance for all my eyepieces to reach focus. The
scope had great optics, believe it or not. Looked to be close to 1/4 wave
spherical. However, despite great views, I could not quite get it to split
M13, which it would have if were truly
a professional grade 4.5" scope. Jupiter did show belting and contrast
was generally good across the board. I highly recommend this scope over
a pair of binoculars for a beginner or child as it can do both planets
and deep sky.
PROS: Most user-friendly and stable
beginner scope with very good optics
CONS: Limited aperture and requires
a table top
70. The
NGT-6 Split Ring Equatorial Reflector (6")
Due to minor mechanical problems that
were subsequently fixed, I have decided to default to Ron
Wodaski's excellent review of this scope. Just clink on the link.
71. The
Takahashi FCT150, f/7 Refractor (2001)
This is an incredible scope with superb
performance and excellent mechanics. It has been recently discontinued
and runs around 13,000 + second hand for the OTA alone. While I have just
begun to test it, I already am thrilled by the performance. The scope is
not without drawbacks. Although fairly short for a 6" refractor (f.l. is
1050mm) it is very heavy, at 46 lbs. This required that I get a completely
different mount for it. In addition
Ed
Ting reports that it takes awhile to cool down, longer than an AP155.
(I haven't noticed that as of yet now that it is milder) It is more expensive
than other 6" triplets. The construction is unique. Metal baffles are even
placed in the oversize dewshield, the 4" focuser somehow seems beefier
and more exacting than other Takahashi scopes, the large metal ring to
screw the finder to is convenient and can also be used to carry the scope,
the camera angle adjuster is smooth as silk, the dewcap is beefy and slides
on and off the scope with unusual smoothness. Focus position is good for
almost all eyepieces with the included extention tube attached to the telescope.
A shorter tube can be custom made for even MORE focus travel which would
allow the scope to work with binoviewers without barlows, etc. (A second
extention tube is provided for straight-through viewing)
Optically the scope is incredible. Tops the list in terms of star test. It has wonderful "snap-to" focus, that is, there is no doubt when you hit the focus point. On Mars for instance, just a tiny jog of the focuser either way, and Mars was completely out of focus, tweak it just right and BAM! Straight from no focus at all to completely crisp. The scope, like the AP155 acts almost like it isn't a 6" at all. Globulars are completely resolved with tiny, tiny pinpoint stars. Even M56 was very well resolved. The 14.2 magnitude star near M57 (second over from the 13th mag. star at the tip, see the link, it is listed) was detectable with DIRECT vision, nevermind averted vision and easy. NGC6904 near M13 was easy and pretty. The double-double particularly striking for the wide gap between the stars and lack of first diffraction ring around each indicating excellent optics and cleaner looking double splits. This scope, like the FS152 seems to beat the seeing. Mars is particularly low and pretty much a waste to look at above 35 degrees north latitude this apparition. However, in moments of clarity, helped along by excellent optics, Mars was particularly crisp through 350X with lots of fine detail in low contrast shaded areas. (I didn't have my Mars map with me so I'm not sure what I was looking at at the time) The particular scope I have did exhibit a very minor amount of focus shift at high power, very mildly annoying, but something that can be fixed if I ever get the initiative to send back such a heavy scope to Texas Nautical Repair. Stars are completely free of false color, including Vega. Overall performance is reminscent of the AP155 f/7, however, the mechanics of the tube are more alluring. Ed Ting, who borrowed this scope, felt that the oil-spaced triplet of the A/P 155 may have led to a tiny, miniscule amount of additional contrast from object to sky than this scope, but generally did not take the scope above 200x on his planetary test. With such wonderful correction to the optics, I would think that this scope would do just as good if not better at resolving features at high power, but I can't say for sure.
More coming...
PROS: Incredible performance for 6"
aperture. Wonderful mechanics, ultimate scope.
CONS: Cost, runs much more than other
6" triplets. Weight: 46 lbs
72. Orion/Vixen
BT-80 Binocular Telescope
I was very surprised, delighted in fact
at what this scope can do for the money. A binocular telescope won't
quite give you double the light gathering of a single telescope, since
you can't really add eye 1 + eye 2 and come up with double brightness,
but effectively the additional perception that you get by providing an
image to both eyes independently is to almost double the amount of light
perceived,
at least making the view comparable to 20% greater aperture, or more. This
is the opposite of putting a binoviewer on a telescope in which case you
lose a little bit of light because of the "split". Here you perceive a
net gain, rather than a net loss. In either case (bino-telescope or bino-viewer)
you gain wonderful fairy-tale views with false 3-d perception that makes
astronomy even more enjoyable than it already is.
The BT-80 consists of two smaller-than-normal 80mm tubes (f/11, 900mm fl, because of a built in teleextender) that are bound together by an easy carrying-handle and finished off with an erect prism unit (45 degree angle) that can take various eyepieces, and can be adjusted for interpupillary distance. The unit is only 11 lbs, but very, very back-heavy making it difficult, but not impossible to use with a camera tripod and head. I used the Bogen 410 head which held it well enough, and was fairly stable, but I wouldn't want to use it with that all the time. The Custom-D Altazimuth mount that is provided as an option from Orion Telescope and Binoculars should work fine, although I should try this on my Universal Astronomics dedicated binocular mount which should work well on that.
I placed a 1x pointing unit on one of the scopes, and I was off and away. The supplied 25mm orthoscopic eyepieces are color coded to assure correct collimation, but I found all my eyepiece pairs were generally collimated from 12mm on up. If you have a problem, the instructions suggest rotating one eyepiece until collimation is a-ok. The supplied eyepieces provide only a 1.1 degree fov, and 36X. This is not adequate. I used 30mm Ultimas (celestron) and was delighted that there was no vignetting at all, unlike what I was warned by Ed Ting about. The prisms must be large enough. the fov now 1.7 degrees, and I was using 30x. Wide and mid views were very, very similar to a Vixen 90mm scope fitted with a Televue binoviewer, and eyepieces which attempted similar magnification. Unfortunately, the BT-80 is a fairly poor achromat, and although stars were sharp, right to the edge using 12.5, 18, 25, and 30mm eyepieces, anything under 25mm gave objectionable purple to daytime objects (and presumably bright night-time objects as well). However, M13 and M71 looked just great even at the higher magnification. M13 partially resolved to pinponts at 72x, about the same as it would single eyepiece at that power in a 85-90mm of greater quality, and about the same as it would with a binoviewer in a fine 100mm scope. Comparing to the high quality 90mm Vixen Fluorite, with the Binovue in place..., this bino-scope did resolve M13 a slight bit better. However, when I compared the view through a 6" high quality refractor outfitted with a binoviewer, there was no comparison whatsoever. . . the 6" trounced this unit, and I believe it would have even if the two 80mm tubes were something high quality like Vixen Fluorites.
STILL TESTING
PROS: Great intro to binocular telescopes.
Lightweight and tripod mountable (to some degree). Low cost.
Interchangeable eyepieces. Well collimated.
CONS: Limited/objectionable high power performance, especially on brighter objects. Too high power with eyepieces supplied, and even optional 30mm Ultimas that I put in there.
73.
Celestron 8" NEXSTAR f/10 SCT:
This is a wonderful scope for the price.
Excellent optics with something that certainly looked close to 1/8th wave
at the eyepiece or a hair better, one of the best SCTs I have run into.
The NEXSTAR mount is excellent but not at all heavy duty. Suffering from
some of the "sloppy" altitude problems (not tight) that I also found at
times on the Ultima 2000, and the LX200 (meade) I ended up sending this
used unit back for repair to Celestron. When it came back it performed
marvelously, almost always hitting the GOTO object in the 30mm eyepiece
I used. Every once in awhile I would touch up the alignment to keep the
scope pointing accurately horizon to horizon. The hand controller is easy
to use, although the initial align takes longer than I would like. There
are a wide variety of ways to get to your object, and the list is long.
The disadvantage is that you cannot move this scope manually, which is
a bear. It is too tempting with Mars floating in my southern sky for such
a short time of night, to just point and go, rather than have to do an
alignment, but in this case, align you must.
The NEXSTAR8 can be had 2nd hand for just a bit over 1100.00. This is exceptional considering how much the Ultima 2000 had run. The Ultima 2000 was better for serious astronomy. Better mount, better drive, less backlash, seemed more "serious" , but this scope certainly worked well. As for objects. M13 of course fully resolved. M31, lots of contrast. M25 Wow! great cluster (cute asterism in the center), M8 with filter. . . just grand. NGC6939.. can see the flock of birds flying, but not as well as in M11 which is oh so rich and highlighted with a red leader star. NGC6946.. tough in light polluted skies, I could make it out with the good contrast of the scope. M57.. saw the 14th mag. star near the ring w. averted vision easily! NGC7331. Easy as pie. M51. Easy find. Did not look for dark lanes, in the light pollution, but general structure easy. M71 nice resolution. M28, slight resolution of this tiny globular hinted at.
The scope runs on batteries or a/c power which is nice. The disadvantages of the scope includes a poor placement of the OTA so that you cant use tiny eyepieces when the scope is pointing near the zenith without straining. Ray Cooper has come up with an extention bracket that he will be selling after market that cures that problem, making the NEXSTAR 8 or NEXSTAR 5 able to pop on and off the mount, slide up and down for better balance, and slide in such a way as to give more clearance for 2" diagonals, etc. Scope is supplied with a nice 1x pointing device, rather than a finder, which actually works out fine. The scope feels less well built than the U2000, but it is very lightweight and easy to transport. The problem is, since it isn't built very ruggedly, I get nervous transporting it, that the altitude will be inadvertantly moved manually while it sits in the car boucing around, and since the alt (and the az) is supposed to be "locked" at all times, I bet this can cause some slop. Another disadvantage is that unlike the LX90 (meade) or LX200, the scope cannot really do good photography long-term as the drive supposedly suffers from some jumping, etc, even when on a wedge. (this is from here-say). It also seems to me to have more backlash than the U2000 had. Overall though it is an excellent visual scope for an excellent price.
74.
7" Teleport
If you read up on the 10"
Teleport then you probably are excited to find out how this slimmed-down
version of Tom Noe's masterpiece turned
out. I will mention mostly the observation reports, and the differences
between this and the 10" model, since they are so similar. I will also
mention some of the things I forgot when reviewing the 10".
The 7" teleport, sports a Zambuto mirror
(focal length 1000 I think, have to double check exact figure) with an
unsually smooth figure. (I won't even tell you what the estimated wavefront
is, as it is uncanningly good, and for comparitive purposes within the
Zambuto and similar lines only, and will just be ridiculed by those who
don't understand this). The whole idea behind this scope was to make it
airline compatible, that is CARRY ON. While the dimensions just barely
make it such (when it is folded down and placed in its case) the
20 lbs is a bit heavy to lug around, but if you have had your Wheaties,
it is do-able. I'm still a bit wary about bringing this in addition to
other carry on bags though, since I don't usually eat Wheaties in the morning.
Suffice it to say though, that it does fold up to less than that 9x14x22"
standard. The extending struts are actually adapted bogen (manfretto)
tripod legs. It takes a bit of fiddling to get these truss poles to extend,
but once you get the hang of it, it is pretty easy. They sometimes "catch",
making extention of the poles difficult, and you also have to be careful
while opening and closing the scope not to let the built-in light shroud
get in the way. It is a marvelous design though, every inch is utilized
to its maximum, reminds me of a mini motor home in that regard. If you
don't travel with it on an airline, and plan on bringing it in a car, it
is so small, it can fit virtually anywhere, even in a 2 seater. Indeed
the 7" design seems to work even better than the 10" in terms of the intelligence
of the fold out and fold up of the unit.
The scope sits pretty low to the ground even when unfolded, but is a perfect height when using a low piano/observing stool. The only problem would have been using the 1x finder, but Tom switched to a pop-on, pop-off Rigel Quickfinder, rather than the lower profile Daisy-site kind (Orion,Televue, Stellarvue), and it sticks up far enough that star finding is only a problem in Dobson's hole- straight up. The finder has its own little place for storage at the base of the unit, and is conveniently placed. Like the 10", the scope comes with electrical stuff.. that is an eyepiece dew heater, a fan for quicker cooldown (hardly necessary with such a thin mirror), and a secondary heater. I find it overkill, but a nice touch. There is an optional folding "tri-stand" that raises the scope up about 6" and makes it more grass-friendly, I didn't know I could purchase this, but I find on my patio, or driveway, the scope is quite stable. I did not try it on the lawn yet. The 7" (and I think the 10, and 14.5") can now be fitted with encoders, and mine was indeed. The encoders are hidden well and I'm eager to use the optional Sky Commander for finding objects. So far I have been star hopping using a 30mm ep.
The performance is quite uncanny. The star test is superb, better than 1/8th wave at the eyepiece. The moon is crisp as can be at 300x. Detail INSIDE the craterlets of Plato could be discerned. The 13th mag. star near the Ring Nebula was easy in AWFUL skies (fog, moonlight). (Next night, mag. 5.3 skies or so allowed me to discern the mag. 14.1 star near the ring) M15 resolved near a gibbous moon. I have a lot more testing to go though, I just started looking at objects in the scope.
The scope comes with a very nice helical 1.25" focuser, and Tom feels he can't do this right with a 2". This limits low power field size to some degree, but the higher focal ratio makes the use of a parracorr unnecessary. Low power eyepiece recommendation would be 22mm panoptic (but too heavy for my taste), 24.5 Meade Superwide, and 30mm Ultima, 32mm Televue plossl. There is very little focus travel in the focuser, but Tom did an amazing job in setting the focus to handle ALL 1.25" eyepieces that I have thrown at it. My nose is a little tight against the scope on the lowest profile eyepieces. Balance is easy to control using screw-in counterweights, but you can also adjust the tension of the alt and az movement of the scope. There is a nice convenient place that 2 extra counterweights are screwed onto the Upper Tube Assembly, along with a small allen-wrench which is used to adjust the excellent Protostar secondary. There is also an eyepiece drawer, as on the 10", with foam that can be cut to fit.
7/13/01 Update: VERY VERY similar performance on deep sky to a 6" apo. Almost identical resolution on M13. So far planetary is slightly better in the Teleport than the 6" apo, with slightly more contrast, slightly easier moon detection (on Saturn). HERE IS ANOTHER REVIEW OF THE 7" TELEPORT by Andre Hassid.
75. The
Televue 76mm APO
I'm thrilled to death that Televue did
this. They took the Televue 85mm and made it smaller, with the Televue
76 the same size as the Televue Pronto, but virtually color-free. Available
in evergreen or white, this76mm APO doublet sports a 480mm focal length
(f/6.3). Roughly the same size as the A/P Stowaway (version 1) and Takahashi
Sky 90.
Mechanically, the scope is nearly identical
to the TV85 Bizarro that I had, from size to function.
I tested this scope on several nights but stuck to the usual suspects this time. M13 did resolve but not quite as well as in the TV85, noticeably better though than the Pronto. I was barely able to detect M57s 13th magnitude companion star off the tip. Jupiter was very crisp with the GRS noted, and Saturns Cassini division was easy and quite contrasty for such a small aperture. Collimation was perfect. The star test was excellent. The Pronto sized carrying case and rugged nature of this scope makes it the perfect airline travel scope. The Sky 90 and Stowaway scopes from Takahashi and Astrophysics have more aperture, for the same physical size, but are more expensive.
76. The
Astrophysics Stowaway 2
What a scope. The best 92mm scope ever
made to my knowledge, the now f/7, 90mm (92mm in actuality) Stowaway is
a slim brother to the A/P 105mm Traveler. This scope IS essentially the
optics of the Traveler, but cut down to 92mm, allowing for the f/7 rather
than f/5.8 optics. The star test is unbelievably good in this scope compared
to the original Stowaway which was hard to judge due to the fast f/4.9
f-ratio. Stars are pinpoint closer to the edge as a result of this slower
f-ratio with almost all eyepieces. I couldn't find any spherical aberration
or other star test flaws, it is beyond my detection with a green filter
at 200x. Until the planets come back it will be hard for me to put the
two
scopes (f/4.9 and f/7) together to make a fair comparison between the two
scopes, but I will try anyway shortly. Meanwhile, mechanically and otherwise
the scope works and performs similarly to the smaller Stowaway, except
it IS 19" long compared to 14" length of the old unit. It weighs 6 lbs,
and seems a tad heavier than the old Stowaway, but is much more "carry-it"
friendly than the Traveler. The dewshield is short like the old Stowaway
which may be a problem on a night with heavy dew. There is a slight difference
the optics, but both are triplets and color-free. However, certainly the
f/7 will likely ( can't tell yet, I loaned my f/4.9 to a friend) do better
as was reported by A/P, but how much better?
So far I have viewed the double double
(amazingly clear, wide, clean separation between components and even shows
the different colors between the stars involved. The Ring nebula (once
again, easy detection of the 13.01 mag. star nearby even in mag. 4.5 skies)
M71 (easy detection, poor resolution) NGC6970/6992 (Veil nebula, beautifully
seen in some light pollution with UHC filter, all 3 components) Vega (clean
and white) M27 (Great contrast) M15 (great deal of resolution in light
polluted skies approx. mag. 4.5 or 4.6, M13 - Total resolution down to
strings of individual stars with DIRECT, not averted vision at 200X, and
good resolution but not quite as impressive at 100x) M52 (GREAT!!! resolved
pinpoints over a dense unresolved remaining cluster, mag. 5.2 skies approx.)
N. American nebula (with UHC filter, nebulosity all over the place, great
contrast but needed less power, I was using a 27mm panoptic) M11.. perfect
pinpoints, NGC7331 - Galaxy EASILY detected in mag. 4.8 skies, shape easily
discerned,
More coming..
Pros: Best 92mm scope ever made, a Traveler
on weightwatcher diet, Superb 2-speed focuser
Cons: Full 19" in length, not as handy
as the old Stowaway
BEST STAR TEST SO FAR.. (all the below are outstanding)
Better than 1/8th wave..
1. Astrophysics f/7 92mm
Stowaway
2. Takahashi
FCT150 f/7 refractor
3. TMB Designed,
William Optics (Yang) 100mm f/8 Fluorostar
4. Zambuto 10"
in the Teleport (Dob)
5. Starmaster
14.5" (zambuto optics) *Currently reevaluating, now showing overcorrection?*
6. 50mm Takahashi
FC-50 & 60mm Takahashi FC-60 (but not the FS78, nor the FS60)
7. Astrophysics
Traveler (2 of 4)
8. Astrophysics
f/6 130mm EDF AND f/6 155 EDF
9. Zambuto 7"
in the Teleport-7
10. 55 &
90mm Vixen fluorites (3 of 4)
11. Celestron 8" (Nexstar)
SCT f/10 (1 of 3)
Below, 1/8th wave or a bit less.. but still outstanding
12.. Televue 102mm
13. FC-100 & &
FC125 & FS128 & FS152 & Sky 90 Takahashis (some minor color
noted)
14. Takahashi CN212
Classical Cassegrain
15. Meade ETX (1 of
3)
16. 70mm Vixen Fluorite
17. Televue Televue
85mm and Bizarro 85mm (2 of 4) (some minor color noted)
18. Intes MN56 Mak-newt
19. Pentax 75mm SDHF
(some minor color noted)
20. Televue 101
(*The first 11 were corrected so well I could barely discern the spherical aberration at all, meaning better than 1/8th wave (approx), all others listed approximately 1/6 to 1/8 wave or better, as defined by Richard Suiter. However, star tests are not perfect by any means, and are somewhat subjective!)
BEST PLANETARY SCOPES SO FAR..
1. 14.5"
2. 16" & 18" Starmaster w. Zambuto and Pegasus optics 2. 12.5" Portaball from Mag1
3. 10" Teleport w. Zambuto optics
4. 8" Portaball with Zambuto optics
5. Takahashi FS-152mm & Currently Testing FCT150mm
5b. 6.1" D155 f/7 Astrophysics EDF
(Two above are close,
TAK seemed better, Ed Ting is testing them against ea. other, and has come
up
with the opposite conclusion)
(Takahashi TSC225 seems to fall approx. here.. as for the CN212, planets were not available)
6. C-14 SCT (not 100% positive, needed better seeing to confirm, brief test only, use this with skepticism)
7. C9.25" SCT Celestron SCT
8. 7" Starmaster with Zambuto optics, and 7" Teleport with Zambuto optics
9. Ultima 2000 8" SCT
10. 5" Takahashi refractor FS128 & 5.1" Astrophysics EDF (planets not avail. when FC125 was used)
11. Intes MN56 Mak-Newt (5" f/6)
BEST BUYS SO FAR.. (of
currently available models)
1. Orion Short-tube 80mm
refractor, $199.95 + small shipping charge (better than ever)
2. Meade ETX - 90mm Maksutov
$595.00 + shipping (better than ever with new drive)
3. Intes MN56 Mak-Newt $799.00
+ shipping/insurance (hi-res. planetary scope + deep sky)
4. Televue 85mm APO - Under
$2,000 including star diagonal (low cost compared to competition)
5. Celestron C8 OTA (SCT)-
Available for under $500 second hand, the C8 optical tube assemblies now
represent an unsually good value and are very versatile.
6. Celestron G5 (C5) Tube
only (fits tripod or GEM) - Available for 400-450 second hand, super portable
OTHER SCOPES... While I have not fully tested the following scopes, I understand they are important in the amateur community, and have knowledge about how they fare, in general. I will include other people's reviews here as well. (look for the links) In addition, a few of these below have been reviewed by Jay Park.
5" Meade ETX and 5" Celestron NEXSTAR - A comparison from the newsgroup sci.astro.amateur
Intes Micro-Alter 603:
I
was able to take a look at this scope and how it works indoors. The
generous mirror travel makes
this 6" f/10 Mak ideal for
binoviewer use. Optics were very sharp. Unit was lightweight enough to
attempt to use on a very sturdy bogen tripod/head combo, although that
is pushing it. It has a handle like the Intes MK67. Coatings looked great,
many baffles. Focuser had some stiction spots. This is probably just about
the best airline portable scope for the money.
Intes MN-61 Mak-Newt: This 6" scope is getting a lot of praise. Apparently it's small central obstruction aids in achieving a sharp, contrasty image. One views through the top of this kind of scope, like in a standard reflector. This apparently produces much better image quality than the Meade or Celestron previous offerings. Readily available, and excellent for photography..as I think it is f/6.
Intes MN-71 Review by David North and Jao Bond
Televue NP101 - 4" REVIEW ON COMPANY 7 WEB SITE
Astrophysics 7" f/7 EDF refractor: Both the f/7 and f/9 latest offerings from A/P have apparently produced some of the best planetary views imaginable for such relatively limited aperture. It takes an unusual night for larger reflectors to be able to beat these babies, from what I am told. The deep sky views seem closer to what one would expect from larger scopes, perhaps 9" or so, because of the excellent contrast. Not currently available.
Astrophysics 10" Mak-Cass: I received this scope but have loaned it to a close astrobuddy to test.
Brandon 94mm : The lens was designed and manufactured by Roland Christen, but the relatively small scope (only 2' long, I think it's f/7) was sold through Vernonscope. It was one of Vernonscope's best offerings. It does show some "color", compared to the latest Astrophysics scopes, but apparently is quite excellent on wide field and high power views. Not made for travelling, but just *barely* airline portable if you get creative.
Celestron C11": I have heard mixed reviews. The scope is generally known to be superb and more satisfying than the Meade 10" models optically. However, I have heard varied reports on it's optics.
Meade 12" SCTs: Again mixed reviews from poor optics, to very satisfying views. The LX200 version is quite popular.
Edmund Scientific Astroscan: Cute, easy to use, wide field scope, but near hopeless at high magnification. Unique and inexpensive. Great for newbies and youngsters.
Starsplitter Dobs: Excellent, just below Obsessions in both look and ease of movement. I personally would recommend Pegasus optics, but you'd probably do well with Nova, or Galaxy too.
Televue Oracle: Even better than the Pronto/Ranger series, discontinued in the early 1990s, and 76mm wide, 6mm wider than the Pronto/Rangers. Also, more color-free than the Pronto/Ranger.
Ceravolo HD145 and HD216: Reputed to be incredible. These high quality mak-newts are fast, corrected Newtonians that can go to low power wide field, or perform at high power with planetary views similar to refractors of almost the same aperture. Large.
Televue 140mm refractor: Reputed to be fabulous in it's views and extremely versatile (it isn't all that big, low focal length)
Edmund Astroscan and Bushnell
Clone: Tried both of these in the store, I can't speak highly enough
about these low cost scopes. The reasons are ease of use and high stability.
They move so fluently and without the "shakes". Plus they are small, tabletop
telescopes that should be on your holiday gift list for the kids. (Have
since reviewwed the Astroscan above)
