The basic question here is: How do you focus in your camera?
Originally, I would focus as best I could by looking through the viewfinder of my SLR camera when mounted on the telescope, and then snap an image and preview it on the camera, looking to see if it was "acceptable." Note that the camera body was used as the "eyepiece" (the eyepiece was taken out and an adaptor was put on the camera to allow it to function as the eyepiece would).
But now I actually looked at the software that came with my camera and I found that I can feed directly into my computer. So, what I did was image a bright star (I think I used Capella) and looked at the images on my computer. I then adjusted the focus in one direction, by pressing the focusing button on the telescope I was using for just long enough for the motor to kick in to move it, and then I re-imaged.
I kept this up until I got as small a stellar disk as I could (signified by when the disk started to get larger). However, this corresponded to only about 10 arcsec, which to be honest, just sucks. It's about half the diameter of Saturn's disk these days.
I know the seeing was better than that, for when I looked at Saturn with an eyepiece instead of my camera, I was just able to make out the Cassini Division, and everything was very crisp about the rings and Saturn's disk. But my camera showed fuzz for Saturn.
I also know that the camera is very capable of producing higher quality images since I've used it for many months in the day and the focus is always very crisp when shooting in the same file resolution (I use highest quality JPEG when I shoot, though I'm just starting to experiment with camera RAW, though the focusing was no better in this mode).
So after that long-winded explanation of what I'm doing, can people suggest ways to improve this poor focusing, or possibly suggest another culprit to look into?
Thanks in advance.