Hi Alex
It is possible but not easy ! Atmospheric distortion is another problem which is why video images such as done with webcams give better results. The guys who are really good at this technique stack hundreds of video frames in programs like Registax to get superb results. Mike Salway " Iceman " has some crackers ... I assume you know who he is ... so do several other members of IIS. Check out their images in the Solar System forum.
Here is a megre effort that I did with my 350D and a Meade variable projection tele-extender and I think a 2x barlow as well. Quite a hefty lot of stuff hanging off the side of the Newt. It is also a stack of images but I can't remember the details now, it was a while ago.
http://www.iceinspace.com.au/forum/a...5&d=1176099791