Telescope Reviews: Celestron CGE 1100 as an imaging platform?

Glad for the clarifications, Marty. That makes things easier.

1) Your imaging experience with the DSLR and the M90 mounted on the 8" SCT will be good experience to fall back on. That allays my concerns somewhat--you're more likely to be able to diagnose problems than pure beginners would be. Plus, you have a much better idea than most what you are getting into.

2) You are right that more aperture will let you go deeper with a given exposure duration, but I still wouldn't jump straight to the 11" for deep sky imaging. It's just hard to work at those focal lengths with that much weight unless you have an AP-900 class mount or better. I wish it weren't true, but it is. I spent most of my first 18 months of imaging fighting with my Losmandy GM-8 and 4.3" refractor. Getting round stars without guiding was challenging even with fairly short exposures (30s), and getting all the resolution the scope and camera were capable of even with guiding was very unusual. And my refractor only had a 715mm focal length. Most of this was due to limitations of the mount. Now the CGE is a more capable mount than my GM-8, but asking it to image with a C11 is right on the edge. For planetary photography I would have no qualms, but for long exposures it will be challenging. It can certainly be done--I've seen the proof--but it wouldn't be my first choice as a deep sky combo. That scope could really benefit from a sturdier (and much more expensive) mount. Obviously, the CGE will have no problems supporting the M90.

3) The CGE-1100 is certainly priced reasonably and is a great visual instrument to boot. I can understand the temptation. I still wouldn't recommend it for your intended use--deep sky imaging with a DSLR

4) I understand your point about putting the LX200 on its tripod, and you may find that the CGE is a little easier (since you don't have to worry about matching a bolt to a hole), but you are also going up substantially in size from an 8" to an 11" so you are gaining bulk and not saving as much weight as you might think. The 11" with two dovetails (one for the scope and one for the off-axis guide scope/M90) is going to weigh around thirty-two pounds vs. forty-six pounds for your current forked OTA. That's a significant improvement, but it's still not trivial to setup a CGE-1100.

5) You don't need an astro CCD camera to take good pictures. If you are initially going to be imaging brighter objects--the showcase type objects--then a DSLR will be able to do very nearly as good a job as a much more expensive CCD camera. No reason to switch here. When you get to the point that you are trying to capture all the resolution the seeing conditions allow on that 16th magnitude spiral in some obscure part of the sky, that's when you need to think about a dedicated astronomy camera. Or if you decide to do emission line imaging since you live under light polluted skies. Nothing wrong with sticking with a DSLR for now.

6) You mentioned that there can't be a downside to more light. I would respectfully disagree with that. The downside is that unless you have a really good quality mount to go with your 11" scope, you will not be able to get pinpoint stars and good tracking. I wouldn't want a scope that large for imaging unless I had a permanent pier and a top quality mount. The CGE is a really nice product, but it just isn't up to this task, in my opinion. Look around the web to find images taken by owners of this scope... Bob and Janice Fera have produced some nice work, but they had it mounted on an AP-1200. Stephen Juchnowski--again an upgraded mount... Shoji Suzuki--using a Tak NJP mount... Check out P. van de Haar's website here to give you an idea of what can be accomplished with this scope when it is undermounted. In his case, he was running it on an Orion Sirius/Synta HEQ5 mount which is significantly less sturdy and precise than the CGE, but you will notice how much better his planetary results are than his deep sky stuff. In my experience this is typical for bigger scopes on smaller mounts.

7) I can certainly understand the attraction of a GEM vs. the Meade fork mount. Polar alignment is usually easier, you can swap optical tubes easily, and there is no problem imaging near the north celestial pole. Better quality GEM's usually have more accurate tracking than a Meade or Celestron fork mount. The down sides are that weight is often higher (due to the need for counterweights), the cost is usually higher, and you have to worry about meridian flip when imaging.

Whatever you decision, I wish you the best of luck. I think a CGE is definitely a good choice, I'd just recommend an 8" optical tube rather than the 11".

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- Jared Willson

Fluorostar FLT-110 w/ TEC optics
Vixen VC200L
Astro-Physics Mach1 GTO
Stellarvue SV80S
Takahashi Teegul SP Mount
STL-11000