To make a long story short, I had sent my new Meade ETX 125 back to
Meade to repair problems with image shift, collimation and other minor
things (like the RA setting circle "belt" was so loose it was falling
off).  While I was waiting, I read many good things about the new
Celestron NexStar 5 and decided to get on a waiting list for it in the
event that Meade did not fix the ETX to my satisfaction.

Yesterday, by coincidence, I had received the ETX 125 back from Meade
and the NexStar!  So, a quick comparison was in order before I decided
which instrument was to stay!

Test #1: Daylight

First, I will compare the overall appearance and apparent quality.

Since the ETX was here first, I will look at it first.  Meade had
explained to me that parts were replaced in order to fix the image
shift issue.  A redesign?  You tell me! The other things like the RA
settings circle and eyepiece holder set screw are fixed and the DEC
setting circle is now set properly.  Good signs so far, but there are
numerous little "scuffs" on the drive base (plastic).  Annoying, but
not really a big deal.  The OTA is clean, as are the optics.  No
finger prints or scratches.  The focuser feels smoother than before.
So, I mount it on the Meade Deluxe field tripod (I really wish someone
would do something about this clumsy adapter plate) and re-assemble the
scope with the finder, batteries, etc.  I take it outside (still
daylight) to do some terrestrial viewing.  I pop in the Meade 24.5 SWA
and look one of those huge electrical pylons that seem to dot the
landscape these days, about 1  mile away.  Looks good.  Nice and
sharp, even though there is quite a bit of heat ripple (L.A. is a nice
92 degress F. today, thank you).  Hmmm, there are 7 vultures sitting on
the top of the power pylon.  An omen?  Let's test for image shift.
Well, upon fine focus, I see NO IMAGE SHIFT!  Ok, let’s put in a Meade
13.8 SWA and take it up to 138x.  Still looks good, though the heat
ripples are taking their toll now.  (Yep, they are vultures!)  I
focus... NO IMAGE SHIFT!  So, let’s for the gusto and pop a Celestron
Ultima barlow under the Meade 13.8 SWA for a whopping 275x
magnification.  I have a vulture filling my field of view
(Ugly SOB, even with the heat ripples).  The image is a little fuzzy
now.  Probably due to the heat.  Anyway, I focus in and out of focus
several times, both fast and slow... ABSOLUTELY NO VISIBLE IMAGE
SHIFT!  I am serious.  I cannot see any.  It may show up a little at
night, so I’ll check it again then.  I really have to commend Meade on
this one.  They really seem to have addressed the image shift problem.
So, I put the 24.5 SWA back in without the barlow and view a
tree about 1/3 mile away.  Very sharp.  I go through all of my eyepiece
combinations as before, and every time I get an extremely sharp image.
Very nice.  All looks good right up until the end.
Yep, there always has to be something.  As I slew back and forth in the
tree to look at different things (the last one being a Praying Mantis
on the tree trunk, very nice!) my slow motion controls starting going
haywire!  I would adjust the controller for slow motion, it would start
to move slow, then all of a sudden it would switch to it’s highest rate
of speed.  I any direction, with any speed setting, it starts moving at
the correct rate, then takes off at full speed!  OK, now I put new
batteries in before I started.  I put yet another set in, check the
battery meter (100%), and retest.  Same thing.  OK, so I plug in the
Autostar instead of the hand controller and test again.  Same
thing.  I reset the Autostar,  calibrate the motors, retest.  Same
thing, only now the gears are are making a "popping" noise when I slew
to the left on RA.  OK, let's try to see what going on.  I take the
scope off of the mount, and "rattle rattle".  What the?  So, I take the
bottom off the scope and out falls a screw.  Hmmm.  Upon closer
examination, I notice that there are three screw holes for holding the
motor and gear assembly in place (FYI: a plastic gear housing with
plastic gears and a motor.  The worm gear and RA axle gear is metal.
The upper base is all metal with plastic sides and cosmetics.)  Of the
three screw holes for the drive assembly, there are NO
SCREWS in them!  It is still staying in place, though!  Well, I install
the only screw that I have (as only one fell out the bottom), button
the bottom back up, and retest.  The noise slewing in RA is reduced,
but not gone.  The slewing rate problem is still present.  Somewhat
dissapointing.

So, basically Meade did a very good job of correcting the image shift
problem and the other items I mentioned, but it looks as though the
drive problems slipped through.  I would guess that it may have already
been that way, but Meade didn’t check it when they had the scope so
here I am with a broken ETX again.  After all of the shipping,
handling, repairing, testing, etc. it probably just finally gave
out.  That’s just a guess.  Anyway, I will put the Meade aside for now
and try to do a star test later when it gets dark.

Now, on to the NexStar:

Even while taking it out of the box, it feels like one solid piece of
metal.  However, be aware that half of what you see in the pictures is
NOT metal.  Half of the visible base and fork arm are metal
and the other is plastic.  BUT, the plastic appears to be only
cosmetic.  In my opinion, this is the only place I want to see plastics
in a scope.  Just for cosmetics.  I know that certain plastics (I
really should call them composites) are quite sturdy and workable, but
I definitely prefer metal.  Even though the NexStar is actually lighter
than the ETX 125, it "feels" heavier.  So now, out with the accessories
and basic assembly. OK, the diagonal goes.  I’m sure it will work fine,
but I am just used to high-end diagonals and the diagonal that comes
with the scope just doesn’t seem to share the same quality "feel".  Now
the red dot finder.  Yeah it works, but the mount is plastic (real
plastic, I WON’T call it composite), so I am going to try and find a
SCT adapter for my TeleVue pointer instead (anyone know if they make
one?).  But, really, these are minor issues.  The adapter on the OTA
for the finder is standard SCT, so you have the flexibility of using
whatever finder you want, which is a plus.  I will just consider
these "upgrade opportunities"!  (Oh, I have been working in corporate
America too long).  Ok, I pop in the AA batteries (x8).   Hey, how
thoughtful.  They load on the top of the base and are easy to insert
and remove, pretty much just the opposite of the ETX.  Also included is
an A/C adapter, also a plus.  I can see how I will want the auto
adapter as well.  So, upon turning the power on I get a red glow from
the hand controller.  I skip the align procedure by hitting "UNDO" and
start slewing the scope in ALT / AZ.  Hey, this little sucker is fast!
Must faster than the ETX.  But, the noise level is about the same as
the ETX 125.  Much quieter than the ETX 90, but about the same as the
125.  However, the gears sound "beefier".  I have no other way to
describe it.  It reminds me of the sound of an LX200, but MUCH
quieter.  This is a good thing.  Plenty of rate adjustments and slew
speeds.  So, I play around with the computer a bit.  Different from the
Autostar.  Let me get the manual... or not.  Hmm, labeled buttons,
intuitive interface, hmmm.  I don’t need the manual!  This is really
easy to use!  Another good thing.  Ok, back to the drive.  There is a
measure of backlash in the gears.  You can actually move the OTA in DEC
a little.  The upside is that this motor drive can be adjusted to
compensate for the backlash.  I did this, but it takes some
experimentation.  If you don’t’ get it right, the scope
either jumps or moves too slow, both of which are annoying through the
eyepiece.  But, I did get it just right.  Very little delay and no
jumping.  I imagine this will be different from scope to scope.  I
don’t have the tripod yet, so I will have setup outside on the ground.
I pick up my accessory bag, and then the scope, and hmmm.  Two of the
little rubber "feet" (you can seem them in the pictures as they wrap up
from the bottom up on the sides for a cosmetic effect) fell off onto
the floor!  Hmm.  Upon closer examination, the glue used to hold them
to the bottom of the base did not hold.  Easy to fix, but a little
disappointing.  Oh well, I will deal with that later.  I take the scope
outside and setup the same way I did for the ETX 125.  Using the same
eyepiece combinations and targets (vultures are gone) I tested the
NexStar’s optics.  I can’t achieve as high of powers as I
did with the ETX due to the shorter focal length, but all looks good.
At 181x with the Meade 13.8 SWA and Ultima barlow, the power pylon
looked sharp, but maybe not quite as sharp as the ETX.
I will have to check the collimation tonight.  Slewing as very pleasant
with this scope.  One VERY NICE improvement over the ETX is that there
is almost no "wiggle" when focusing or touching the scope.  You can rap
on the OTA and it dampens in under 2 seconds, and that was with at
181x.  A very desirable advantage over the ETX.  (on the ETX, even at
low powers, the image "wiggle" even with the lightest touch on the
focuser).  After performing the same test on the focuser as I
did with the ETX, I can report that there is almost no image shift with
the NexStar.  Very slight at 181x, but if you were not looking for it
you would not notice it (The repaired ETX 125 has NONE even at the
highest magnification).  Basically, when focusing, slewing, correcting,
etc. the NexStar is as stable as it gets.  No joke, this scope has a
more stable image than my Celestar 8 on the wedgpod.  Of course, the
scope is sitting on the ground right now, but at least we can say that
the base is solid, even though there is play in the gear train!

So, that’s it for the first test.  I will follow up with a night
viewing test and a pros and cons comparison list of both scopes.

As far as my initial impression goes, it looks like the NexStar may
stay.  I just can’t bear sending the ETX back yet again.  Apart from
the rubber feet falling off of the NexStar, the quality seems
top notch.  Hats off to Celestron.  We all said that we would have been
happy to pay a little more for better mount on the ETX.  Well, here you
go.  In my opinion, I think it is well worth it.

I actually wrote this yesterday, but I am sending it today.  I will
follow up with a dark sky report shortly.
 

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