Good point Mike, though I guess the learning starts right here then with working out how to open/convert that file
Some FITS resources are here:
http://www.artsnova.com/astronomyimages.html
Alternatively, here is a link to the file converted to a 16bit .tiff
www.mudgee.net/ot/oriontif.tif
The file poses some fun challenges, there are some troublesome gradients, a bit of trailing and some colour issues that all need work.