Opinions on Meade 12.5" F4.8 Dob

I'm considering this scope off Astromart, for sale by someone within easy
driving distance. He's asking $750, which seems a little high for a scope
that sells on Astronomics for $845 + $79 in shipping. I'll save some bucks
on the price and not have to pay shipping, so it's a savings nonetheless.
Scope is allegedly 8 months old.

Are the mirrors in the Meade 12.5" generally pretty good? I'm sure that the
mount will need some TLC and eventually I might build/buy a truss structure
for it, but I've learned how to doctor the cheap structures to work
acceptably well.

I've also considered the GS 12" F5 which is "pretty close" in price. What
say you? Should I expect the Meade mirror to be better than/same as the GS?

-Steve Paul

Troll, PLONK

Troll, PLONK

Are the mirrors in the Meade 12.5" generally pretty good? I

Hi:

Amazingly good, actually. When I bought one back in 1994 I was expecting
something similar to the Coulter Odyssey I. Nope. One look at Jupiter with the
Meade and I was blown away. Yes, you will have to do some work to optimize the
scope. The most important thing is replacing the nylon azimuth and altitude
bearing pads with Teflon. Magic Sliders work fine. The plastic focuser is also
a candidate for early replacement--though the 1.25" version is useable...the 2"
is pretty horrible. Some also shipped with 30mm finders...you'll certainly want
to replace one of these with a 50mm finder and/or Telrad. Finally, you'll
probably want to rig a simple balance weight system of some kind. As most folks
know, I ain't exactly a dob kinda guy, but I have very fond memories of my
Meade 12.5.

OTOH, I've heard some very good things about the GS. If you like dobs, I don't
think you can go wrong either way...though the GS probably will require
considerably less fine tuning.




Peace,
Rod Mollise
Author of _Choosing and Using a Schmidt Cassegrain Telescope_
Like SCTs and MCTs?
Check-out sct-user, the mailing list for CAT fanciers!
Goto http://members.aol.com/RMOLLISE/index.html

"Rod Mollise" wrote in message
...

you will have to do some work to optimize the
scope. The most important thing is replacing the nylon azimuth and
altitude
bearing pads with Teflon. Magic Sliders work fine. The plastic focuser is
also
a candidate for early replacement--though the 1.25" version is
useable...the 2"
is pretty horrible. Some also shipped with 30mm finders...you'll certainly
want
to replace one of these with a 50mm finder and/or Telrad. Finally, you'll
probably want to rig a simple balance weight system of some kind.

Right on the money Rod. The mirror seems very nice indeed. The focuser is
definitely junk, and the Naglers use up almost all of the travel outward.
Glenn (previous owner) installed a spring tension system like the Orion
Correct Tension and put magic sliders under the altitude bearings, that seem
to work out pretty well. The base needs some work, but compared to the 16"
Meade, the 12.5" is way better in this regard (it is at least usable, where
the 16 was beastly). Glenn also put a carry handle on the OTA, although I
feel it needs to be moved closer to the balance point. Not sure why, but he
has it back a little too far toward the primary for a one handed carry. At
55 pounds, a one hand carry is doable for me. Well positioned carry handles
is something I'd like to see on all the Dobs 10" and over. They're cheap
enough that it makes sense to me to have them included. Even the XT10 would
be an easier carry with a handle or two. Same with the bases. The XT base
has a single handle which is difficult at best, and the Meade has two "slit"
style hand holds, but they are in uncomfortable carry positions. Generally I
think you need one at a heavy point and a second at a light point to help
with maneuvarability (sp?).

It was nice to get a few hours of clear skies to try this out on the very
first night, and to be able to do a reasonable collimation. The seeing
wasn't great, but Saturn held up at 170x and the Trap E and F were easily
detected. The extra aperture over the 10" definitely helped with seeing the
dark rift in M81, and M43 just keeps getting better and better with more
aperture. I'm pretty happy with the optics.Tomorrow and Tuesday look
promising on the CSC and Weather forecasts. I just wish I had a replacement
focuser on hand.

Stephen

Stephen Paul made the following observation

snip
the Meade has two "slit" style hand holds, but they are in uncomfortable
carry positions. Generally I
think you need one at a heavy point and a second at a light point to help
with maneuvarability (sp?)
unsnip

I have gotten into the habit of carrying my 12.5 inch Meade Starfinder
dobsonian mount by lifting from under the ground board. Then, with arms
outstretched and hands gripping firmly, the two OTA altitude bearing cutouts
slip nicely under my arms at the armpit.

Besides being the easiest way to maneuver, this stance was adopted because
when installing digital setting circles, the very secure azimuth axis bolt
is replaced with an azimuth bolt which is attached directly to an encoder.
This connection is far weaker and, at least in my opinion, is not
sufficiently strong enough to bear the weight of the ground board without
ripping apart. Not good. The rascals cost something like $60 dollars to
replace! So, by supporting the mount from the bottom up, this risk is
eliminated.

Congratulations on the new scope. I've had mine for more than 5 years now
and am still upgrading and optimizing it. . .but I love every second of the
process.


Martin

Martin,
What did you do for a focuser?

--
-Stephen Paul

Stephen Paul asked:

What did you do for a focuser?


I ordered one from http://www.e-scopes.cc/ and when its ravel was not as
advertised, raised the bottom of it off the tube with 1.25 inch nylon
spacers (one located between the tube and the base of the focuser at each of
the four corners of the focuser assembly. These nylon spacers are available
at any complete hardware store. I got mine at Ace Hardware. When the nuts
that are threaded on the small bolts which pass through each of these nylon
spacers are tightened up, the assembly is attached very rigidly to the
scope's tube. I then sealed the newly created 1.25 inch space between the
base of the tube and the base of the focuser by wrapping it with black
electrical tape which blended in perfectly my the scope's tube that I
painted glossy early last spring. The focuser is very nice and has very
smooth movement with no discernable image shift.

I should also point out that it was necessary to enlarge the hole in the
side of the tube which the focuser's drawtube passes through as the one that
Meade cut in the side of the tube for the cheap Model 77 2" plastic focuser
the scope comes with was too small for the new focuser's drawtube to pass
through. I think you will probably end up having to do this for any
replacement focuser you purchase as Model 77 plastic focuser's drawtube is
just wide enough to permit the insertion of a 2 inch eyepiece with no room
left over. You'll see what I mean when the time comes.

Another note, I bought the one from e-scopes to save some money since it is
only $79.95 with shipping included. While my modifications worked just
fine, if I had it to do over again, I would purchase the 2" all-metal rack &
pinion focuser from:

www.telescope.com

This focuser has a racked-in height of 3 7/8 inches and a focus travel of 3
inches. That reaches a racked-out height of almost 7 inches which should
cover most of your EP's. It is $99.95 without shipping charges.

I would be interested in hearing how you resolve the great "replacement for
the Meade cheap plastic focuser enigma."

As an aside, you can find lots of good upgrade info at www.mapug.com
There is also a yahoo group for Starfinders at
http://groups.yahoo.com/group/Meade_Starfinder/


--
Martin
Remove "ilikestars" from email address

Many people rail at the large Meade scopes and at the Odysseys for having bad
components. That was, however, the basic idea of a Dobsonian scope - simple,
inexpensive, but with a good (or at least decent) mirror. Value was the bottom
line with these. And it is a great hobby to upgrade these, as well as a very
rewarding boost in observing.
Clear, Dark, Steady Skies!
(And considerate neighbors!!!)

"Wfoley2" wrote in message
...
Many people rail at the large Meade scopes and at the Odysseys for having
bad
components. That was, however, the basic idea of a Dobsonian scope -
simple,
inexpensive, but with a good (or at least decent) mirror. Value was the
bottom
line with these. And it is a great hobby to upgrade these, as well as a
very
rewarding boost in observing.

I agree. Didn't mean to rail the scope. For the price of the mirror set
alone, you get a working telescope. No complaints, just observations on what
needs fixing.

- Stephen