M74 - the Grand Design Spiral Galaxy in Pisces
M74 - the Grand Design Spiral Galaxy in Pisces
M74 - the Grand Design Spiral Galaxy in Pisces
M74 is the prototype of "Grand Design" spiral galaxies - galaxies that have distinctly defined spiral arms. Telescopically, M74 is relatively large - at 10' in diameter, its about 1/3 the apparent diameter of the Moon. Because of its fairly large size, it ends up being the second lowest surface brightness of all the objects in Messier's catalogue. As such, it is a challenging object for astrophotography.

Be sure to click on the image to see the full version, as there are over a dozen small background galaxies peppered throughout the photo.

In this image, North is Up. This image is cropped to 60% 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 Byers Gear
Guiding 80mm f/11 guidescope with PHD Guiding
Camera Canon 450D - Gary Honis modified
Exposure 206 subexposures of 180 seconds each at ISO 1600 - over 10 hours total
Calibration 30 darks, 30 flats, 30 bias
Date December 25, 26, and 27, 2011
Temperature 43F on 12/25, 45F on 12/26, 48F on 12/27
SQM Reading
Seeing 3 of 5 on all three nights
Location Pine Mountain Club, California
Software Used Images Plus 4.0 for camera control, calibration, stacking, and digital development. Images Plus 4.5 for Advanced Richardson-Lucy deconvolution, multiresolution sharpening, smoothing and noise reduction. Photoshop CS5 used for levels and curves, color correction, selective color, high pass filter, star shrinking, lab color, saturation adjustments, screen mask invert, lens correction, and smart sharpen. Gradient Xterminator for gradient removal. Carboni Tools for additional saturation adjustments, noise reduction, and smoothing. HLVG for additional color correction.
Notes As this can be a difficult object to photograph, I am very happy with the final result. This image now represents my longest exposure to date.

An earlier processing of this image was chosen Digital Astro Challenge Photo 2nd place for January 2012 in the Galaxy Category.