Chris, looks a bit like you're clipping the black end of the histogram as that field has lots and lots of stars, and it should look a bit more like a star field. Nice effort all the same.
Have a look at a thread I started recently about cameras here
http://www.iceinspace.com.au/forum/s...d.php?t=145048
The moral of the story, echoing that above, is that it doesn't matter what you use, it's up to your skill to make the most of it. It's all possible.
Regarding crop factor and full frame...your focal length doesn't actually change with crop sensor/full frame, it's just that the FOV is that much larger with full frame. It's not quite the same thing. Assuming pixels of the same size in each camera, the angular resolution is the same with the same scope.