Process 4 of my M51 data from 2010.  I was advised that the blue could come up a little, so had a little 'tweak'.  I think it works well!  This is exactly the same data as the previous image.

Date: 2010-05-12
Scope: Vixen VC200L @ F/6.4
Camera: SXV-H9
Exposure (L): 19 x 600 seconds - 1x1
Exposure (L): 23 x 600 seconds - 1x1
Exposure (R): 6 x 180 seconds - 2x2
Exposure (G): 6 x 180 seconds - 2x2
Exposure (B): 6 x 180 seconds - 2x2
Guidescope: Televue GenesisGuidecamera: SX Guidehead