Just one thing, I asume that the photo was taken as a JPEG, check your White Balance on your camera, you should have it set on Daylight, from the green tinge, it looks like it is set to Tungsten or something other than Daylight, just a thought......disregard if you shot RAW's, white balance dosen't matter then.
Usually with Omega, I do 60 second subs at ISO 800, RAW setting, then combine the shots with appropriate Darks and Flats.
See here:
http://www.pbase.com/takman2/image/70821267
Cheers