The Comet Holmes image is a stack of 11, 2 minute exposures taken 2007-12-01. ISO 1600, 500mm focal length. Canon Rebel XTi camera. 4" f/5 refractor. Contrast enhanced (histogram stretch). Some of the glow around the bright star is due to thin clouds passing through during some of the exposures. Moon comparison shot was taken the 18th of November with the same equipment.