My first image post in this forum

I am still a beginner so any suggestions and comments for improvement are welcome, especially for the post-processing.
Nikon D80 on a tripod, no tracking, 50mm f1.8 lens at f3.8, ISO 800.
50 x 10s exposures stacked in Iris, 10 dark frames subtracted.
Post-processing in Iris (stretching), Photoshop (curves and levels) and SBNRG (noise reduction).
The colours are probably not right as I am not sure how to do RGB balance in Iris for my camera:
http://www.iceinspace.com.au/forum/s...ad.php?t=21161
Some minor star trailing and coma in the edges is visible, need shorter exposure and smaller aperture. Or tracking would even be better