Best entry level scope for CCD Imaging??

There are enough of you out there that have tried with limited success different scopes; Refractors. Newts, Catadioptric. what is your final analysis as a competent contender, Nexstar 11", Borg, Tak, Meade LX 200 ?? I am confused?? I plan on getting a Starlight Express camera ,should I not abandon my TV 102.. any suggestion would be appreciated, Maybe "entry Level" is not the right term I should be using here.. thanks all.. John M
PS. Any suggestion on a sturdy enough mount for CCD work:
CI-700 Great Polaris Losmandy GM 8/11 APO 600 EGTO ??

Hi john,

Almost any telescope will work for CCD imaging. The real decision is what you will want to do and how you intend to do it. for example, Do you have a flip mirror? If not then it can be frustrating trying to centre something on your CCD chip without a GOTO mount.

With a CCD it is important to match the pixel size with the telescope focal length. If you have already made a decision as to which camera to get, then you should look at a telescope to match. for more information on this, go to the apogee website at http://www.ccd.com/index.htm and click on the 'CCD University" link. That is a very useful and informative set of pages.

Regarding mounts, that will depend on what telescope you have. A cat will require a smaller mount that a newt since it is more compact. As a general rule, get a mount that is rated for a size larger than the scope you will be using.

Hope this helps.

Maurice

Here's my advice, take it for what it's worth.

Start with short focal length imaging. This means you are a bit better off staying away from the standard SCT's. It is far easier to acquire good images, center objects on the chip, etc. with a shorter focal length than with a longer focal length.

When starting out in CCD imaging, you need to focus on learning the basics or you will never get anywhere. With a short FL, you can easily master guiding, focusing, etc. and then spend the most time where it is needed--image processing. Learning image processing is one of the most difficult parts of CCD imaging. Plan to spend a lot of time learning good processing technique.

A second major thing to make sure you get right is your mount. A good quality mount, properly rated for your load, is critical. I would stay away from the CI-700 or GP. They are of lower quality, and you will spend a lot of time just trying to make them work well. The Losmandy mounts now have an improved worm, and the quality is much better. If you have the money, spend as much as you can on the mount. The AP600 is a great choice, but if you want to get a mount that can carry heavier loads in the future, try the 900. The Takahashi mounts are excellent, but a bit clunkier to use--no nice keypads, etc--although they do work very well with The Sky. I would recommend an EM-200 or NJP-160.

As for the CCD, the Starlight cameras are OK, but stay away from the single-shot color. The colors are never very good from these cameras; you are far better off with color filters and a monohrome CCD. The HX-916 would fit here. Frankly, I would steer you towards the new SBIG ST-2000XM. The main reason people have bought the Starlight Express cameras in the past was that they were less expensive. The new SBIG ST-2000 uses the same inexpensive Sony CCD as many of the SX cameras, and also has the built-in guider chip. Anyone who does not like this feature has never used it...it is incredible to have a built-in off-axis guiding chip. It is also very easy to use for a beginner and solves a ton of problems caused by off-axis guiding.

The concepts are simple--keep it simple but high quality and the initial learning curve will be smaller and the results more gratifying. You can move up to more difficult types of imaging later--like the long FL hi-res work. Your TV-102 is a great place to start. In fact, my first telescope that I learned to image with was a TV-102 several years ago...

Hope this helps a little,

Jeff Hapeman

Hi John,

maybe you are interessted in that article about ccd and telescopes. With sortable comparison of the common CCD cameras...

http://www.licha.de/AstroWeb/articles_fullsize.php3?iHowTo=11

CU
Tom

This is a big question.

In one sense, you already have a superb scope for getting started - a small refractor. The only thing that would make it idea is a shorter focal length (shorter focal lengths are less demanding of mount and operator). I believe there's a .8 reducer/flattener for the TV-102, and that would solve that. So by that criterion, you are set!

In terms of a mount, what you are looking for is low periodic error and smooth periodic error. No sudden jumps or errors. The newer G-11s have better worms and gears, and should be fine. All of the Tak mounts are great for imaging; it's a matter of picking one to match your chosen scope. AP mounts are great, too. The CI-700 is so-so, but it's a good choice for someone who doesn't mind tinkering with the mount - maybe changing out some bearings, re-lubing it, etc.

If you can specify what you'd like to do in imaging, I could be more specific about what might constitute and ideal scope and mount for _you_.

Ron Wodaski
author of "The New CCD Astronomy"
http://www.newastro.com