Pinwheel Galaxy M101 in Ursa Major - DSLR
Galaxy M101 is large but faint, with only a vague smudge visible though small telescopes from the suburbs.  Only with larger telescopes from a dark rural
site can one detect the hint of spiral structure.  At a distance of 27 million light years, M101's huge size of 170,000 light years is 70% larger than our own
Milky Way Galaxy, making it one of the largest known disk galaxies.   With long exposure astrophotographs such as this, striking asymmetry of the extended
spiral arms is revealed. The wide-field image (above) shows several smaller background galaxies, including the irregular spiral galaxy NGC 5474 in the upper
left, edge-on spiral NGC 5422 in the lower right, and two elliptical galaxies in the upper right.

wide-field image above combined eleven 8 minute exposures with a Hutech-modified Canon 6D DSLR through a TEC140 telescope on an AP 900
GTO mount, for a total exposure time of 88 minutes.  The
high resolution image below combined nine 10 minute exposures with a Canon 60Da DSLR
through the same TEC140 telescope, for a total exposure time of 90 minutes.  The exposures were calibrated with just darks for the 6D image and both
darks and flats for the 60Da image. Image acquisition, calibration, and stacking for both imageswas performed with Maxim DSLR. I think that these images
compare favorably with my cooled dedicated CCD images, that you can see by clicking
Music:  Maybe I'm Amazed, Paul McCartney
click on image for larger size
click on image for larger view