Hi Paul,
that's actually quite a good image.
The center of the galaxy is overexposed but could be improved by
only using RGB data & no Luminance.
The blotchy background can be fixed easily as per here:
http://bf-astro.com/backgndrepair.htm
I get the prize for the worst NGC1097 when
I tried 8 years ago with a DSLR -
13 frames at 5 minutes each at ISO 800
from a light polluted location.
I won't even link the pic it was so bad but it's in my Flickr photos.
cheers
Allan