M31, The Andromeda Galaxy
This is ye olde Andromeda Galaxy -- nearest large galaxy to the Milky Way (approx 2.5 million ly away). It's apparently similar to ours in size and structure. M31 is so bright that it can be seen with the naked eye from dark skies, and I regularly catch it through binoculars even from downtown Toronto. It's so huge that it doesn't fit in the field of view of my CCD! Andromeda also has a couple of companion galaxies -- M32 is the small one in the upper portion of the frame, and M110 is peeking into the frame at lower left.
This was my first stab at LRGB using the QHY9 as panchromatic Luminance (with IDAS light pollution filter) and an old DSLR image from my Canon as RGB. I'm not thrilled with the colour balance, but the LRGB detail enhancement worked out pretty well.
Forgot to use the FLT field flattener on this one.
12x10 minute frames of luminance with the QHY9 cooled @ -25degC, 18x5min frames of RGB colour with the old Canon 350D. Stacked in DeepSkyStacker, processed in PS CS2.