Here is an article I found on matching telescopes to cameras.
http://www.astro-imaging.com/Tutorial/MatchingCCD.html
Get it too oversampled or undersampled and it will never look right. I've been told 2 arc sec per pixel is a good number for DSLR's. I've been doing some research in this area to try and optimize my set-up. This link is a bit heavy on the math but has a ton of good info on noise and other info on how the cameras work differences between the brands that help or hurt astro work.
https://theory.uchicago.edu/~ejm/pix.../noise-p2.html
I've been trying to wade through it. Lots of info there.
Griz