[gregbradley]

Thanks Heath.

A couple of points that may help.
Firstly a 5D is a full frame sensor and a very large chip. Virtually no scope except an RC or corrected Dall Kirkham scope can handle that size without a field flattener. You have some evidence of star issues in the top right corner which comes from coma. A field flattener with your scope will help.

Secondly because it is such a large chip you are getting bad vignetting in the corners. This is normal with a large chip camera and you need to take flats to help with this. I use a white Tshirt put over the end of the scope and take a very short exposure like 3 seconds at dusk. Take 3-5 of these and combine them using median combine.

Similarly use a dark which is an exposure with no light for the length of the exposures you will be using. Take at least 6 and sigma reject combine to form a master dark. It has to be the same expoure time and ISO. So decide on a standard exposure time and ISO. Many use about 5 minutes and ISO800 or 1600 for DSLR imaging. I wouldn't use less than ISO800 as you would be wasting time in extra exposure time.

When you use darks with a DSLR you use adaptive darks. Images Plus has that facility and it scales the darks to match the exposure it is being used with.

Thirdly, you have done a total of about 16 minutes of exposure time.
This is good for starting up and getting used to your gear but really to make any image it takes more like 1-12 hours total combined exposure time to get a decent enough image. The brighter the object the less you will need, also the darker the skies you are imaging from the less also.

So in summary you need;

1. A flattener for you scope.
2. Standardise your exposure lengths and ISO and use them.
3. Create darks for that exposure/ISO
4. Make flats for your imaging setup using a white T shirt and taken at dusk. You want 1/3rd of a histogram exposure so check the histogram until you get that (usually the light is starting to get quite dim).
5. Take longer exposures and lots of them.
6. Use Images Plus as this is the best DSLR image processing software.

I hope this helps.

Greg.