M33 is the third largest galaxy in our Local Group of galaxies which includes M31 (the Andromeda Galaxy), and our own Milky Way Galaxy. Visually, the galaxy is quite large - about 70' x 40'. This makes the galaxy a bit larger than the full moon. However, unlike the Full Moon, M33 has a very low surface brightness, so it is quite challenging to see as well as to photograph.

The Triangulum Galaxy has many H2 (Hydrogen Gas) regions. In this picture, you can see these H2 regions as the magenta colored areas. Similar to the Orion Nebula and Lagoon Nebula, these regions are areas of star formation.

In this image, North is to the Left. This image is cropped to 95% of the original full frame.

Exposure Details
Lens	Celestron C-8 SCT with Celestron focal reducer
Focal Length	1260mm
Focal Ratio	f/6.3
Mount	Schaefer GEM - 7 1/2
Guiding	80mm f/11 guidescope with PHD Guiding
Camera	Canon 20Da
Exposure	220 subexposures of 180 seconds at ISO 1600 - 11 hours of total exposure
Calibration	30 darks, 30 flats, 30 bias
Date	October 19, 20, and 21, 2011
Temperature
SQM Reading
Seeing	4 of 5 on all 3 nights
Location	Pine Mountain Club, California
Software Used	Images Plus 4.0 for camera control, calibration, stacking and Digital Development and multiresolution smoothing. Photoshop CS5 used for flat fielding, curves, color correction, saturation adjustments, star shrinking, noise reduction and high pass filter. HLVG for additional color correction, Carboni Actions for additional saturation adjustments and noise reduction.
Notes	I had an extremely difficult time processing this image to my satisfaction. Ultimately, I processed it a total of 7 times before I was happy with the color balance, detail, and saturation. In this final image, I am very pleased with the detail I was able to bring out, as the image is quite sharp and can be enlarged a great deal to see many individual stars (which are 3 million light years away!) and it still retained good faint detail in the outer regions. Some day I may try to add some Ha data and capture the star formation regions even better.