M51 wide field

Monochrome inverted  What Is It?  What It Is


M51 Galaxy in Canes Venatici 
Date May 5-8, 2010
Exposure LRGB 340:30:30:30 (cropped; 7.1 hours total)
Camera STL11000M with Astronomik filters
Telescope ASA 10N f/3.7 on AP900GTO CP3
Guiding External guide head with 50mm MiniBorg
Processing MaximDL,  Photoshop CS, AstroActions
Comments Cool and clear, some thin high clouds, good seeing (FWHM 3-4)