Click to see my earlier processing attempt of this image.

Object: Whirlpool Galaxy, M51
Date: March 7, 2002
Equipment: 10" SCT at F/3.3, HX916 CCD, G11 mount, ST-4 autoguider
Exposure: LRGB 30:20:15:20 minutes, all exposures binned 1x1
Processing: Photoshop, mild Unsharp Mask. 
Comments: 4.5 arcsec seeing with thin clouds that finally covered up the sky

Copyright 2002 Paul Kanevsky