Upgrading to 12" or Other Possibilities
Subject: Upgrading to 12" LX200 or Other Possibilities? --part 1 of 4
From: Doc G, Date: March, 2000
Lawrence Harris wrote:
>I unexpectedly find myself in a position to upgrade from my 10" LX200 to
>a new 12" LX200, assuming I can sell the former at a reasonable price.
>Does anyone know of any significant problems with the 12"? I would like
>to know something of the spec, such as whether the base is the same size
>as the 10", and whether my wedge would transfer or whether a
>new one is required.
If you have a fine and working well LX200", I would strongly suggest you think carefully about moving up/sidways to a 12".
I started with an 8" and got aperture fever right away.(G) I went to the 12". I found the 12" to be very much more difficult
to use, less reliable and mechanically much less stable.
Then I got a 10" f/6.3 to complement the longer focal length of the 12" f/10. I found the 10" to be "just right." It has fine
optics, is still "sort of" portable and is stable enough to make imaging reasonably possible.
Note that the 7, 8, 10 and 12 share the same base and drives. With the 12" some shims are inserted into the fork to make it
wide enough to carry the larger OTA. It is my personal opinion that the basic mechanics, the bearings and drives, are suitable
for the 8 for which they are designed, but more marginal for the 10" and significantly too undersized for the 12".
Aperture fever can do you in at some point. So I am suggesting that you fully utilize your 10" and make a thoughtful decision
before moving to the larger sized OTA.
Rather detailed discussions of the mechanics of the LX scopes can be found on my website.
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Subject: Upgrading to 12"LX200 or Other Possibilities? --part 2
From: Al
Hi Chris, I don't know for sure that these heavy duty and high priced mounts are really necessary for the C-14. I own a CM-1400
and it works quite well with the 14" OTA--See my review at:
<http://www.cloudynights.com/>
I'm not going to tell you that this mount is the best thing since sliced bread...as a matter of fact, the Losmandy G-11 is
a far better mount. What I am telling you is that for the price, you can't beat it. If you shop around, you can buy a CM-1400
complete for $5,000...OTA, mount, tripod, everything. What you get is a very sturdy mount and a superb OTA. I have used this
rig for both casual viewing and for imaging...no big problems. Additionally, you can add a Fastar lens to the scope and do
imaging at F/1.9 unguided. I think that this rig has a lot to offer over the 12" LX200.
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Subject: Upgrading to 12"LX200 or Other Possibilities? --part 3 
From: Chris Vedeler <cvedeler ix.netcom.com>
Hi Al, The CM-1400 is a fine setup and for the money is a great deal. I'm very impressed with the optics of the C14 I have.
Very nice. But, if you are serious about imaging, especially at the almost 4 meter focal length of the C14, you really need
a very serious mount. Touch the focus knob of the C14 at 200x and watch how the stars dance around. I see this with my Paramount!
My 10" LX200 isn't as bad. To get those nice round stars on a photograph or a CCD image you need a serious mount. At f/1.9
you have a lot more latitude for wiggles and giggles of the mount. If you plan on using the Fastar setup then the CM-1400 is
probably all you need. After having used a Paramount and C14 for 2 months now, I personally would lean towards the 16" LX200.
I've heard about the LX200's problems too, but I've also heard from people that are quite happy with them. The Paramount with
a C14 is not as stable as I would like. My 10" LX200 is more stable. The pointing with the Paramount is poor to terrible (with
a C14 attached) without the use of TPoint. Out of the box (not using HPP) my 10" LX200 could point to within 4 or 5 arc minutes
across the sky when properly polar aligned. The Paramount with a C14 on a dovetail mount without TPoint gives about 15 - 30
arc minute pointing when crossing the meridian. Crossing the meridian is the kiss of death with the Paramount. This is due
in large part to the flexure between the mount and the scope, but a 16" LX200 certainly wouldn't have this problem. The good
news is that TPoint works magic with the Paramount and will bring the pointing down to the advertised 1 arc minute RMS, but
it takes a pretty serious effort to configure the setup to get to that kind of pointing.
It is not as easy as a LX200, and the LX200 will point much better without the use of TPoint. I don't know how well the 16"
LX200 would respond to a good TPoint model, but I suspect it could get pointing close to 1 arc minute. On the up side, the
Paramount does have pretty phenomenal tracking. 5 arc second periodic error is conservative. I doubt the 16" LX200 could come
close to it. But all things considered, and the fact that aperture is a pretty serious deal in astronomy, if I had the proper
pier location (mine is too close to the center) for a 16" LX200 in my observatory I would consider getting one.
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Subject: Upgrading to 12"LX200 or Other Possibilities? --part 4 of 4
From: Joe Hartley <jhbrainiac.com>
Count me as a happy 16" LX200 user. One thing to remember is that it's really a different scope than the 7"-12" LX200s. The
drive trains are different, as is the fork. The basic concept and operation is the same, but the 16" has a few extra features
and seems a but more robust. As the flagship of the Meade line, I wouldn't expect much less.
As the Topical Archives will show, I've had to do some routine maintenance and tweaks to things, but overall, it's a superb
scope. Last night we had a great night with it. Virgo was well-placed for observation for the first time since we got the scope,
and we were literally giddy with the abilities of the scope last night. We logged a record number of objects last night, most
of which were galaxies, just because we could! For our visual use, pointing accuracy was very good. We were consistently getting
objects within the 25-30' field of view of our UO eyepieces. That's good enough for us - we've never used the high-precision
pointing which is how I think you approach the 1" accuracy.
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