This is M101, a nice spiral galaxy near the handle of the big dipper. It is known as The Pinwheel Galaxy for obvious reasons. It is approximately 25 million light years away from us. The above combined 25*4 (100 min) DSLR pictures, with 36*5 (180 min) CCD = 280 total minutes (4.66 hrs) total exposure time. I weighted the combination heavily towards the better CCD image (75% CCD, 25% DSLR). The CCD frames were acquired April, 2010 from the Davis Mountains. Takahashi TOA 130 Telescope (a 5" APO refractor) with reducer, AP 900GTO mount, and QHY8 CCD Camera & normal workflow. I also ran this through Drizzle Image Processing and AIP4Win's deconvolution filter to enhance the detail in the dust lane area.
Left, Click on the icon for the full sized image of the above.
Old: M101 from NHAC Magby site
First field trip with the Astro-Physics AP 900GTO mount. I experimented quite a lot with the guiding and I think it was pretty good. There's slight elongation that's more due to optical issues with the reducer than guiding issues I believe. The real test will be with the flattener. I had to use the reducer this night to get the Moon & Venus in the same frame, BTW.
Image above is a combination of 25x4=100 minutes exposure using the Canon EOS 20Da (unmodified), ISO 800, Takahashi TOA 130 (a 5" APO refractor) with reducer, Astro-Physics AP 900GTO mount. Transparency was mediocre at best, but you can do a lot with over 25 frames. My current image processing workflow is here.
This is M101, a nice spiral galaxy near the handle of the big dipper. It is known as The Pinwheel Galaxy for obvious reasons. It is approximately 25 million light years away from us. You can see another near-vertical galaxy on the upper left which is PGC 49919. See the wider image below for some additional galaxies. The other HAS Pix from 4/29/2006 are here.
M 101 - Wide Angle View
How many galaxies can you see in this wider view of the above image? The easy ones: lower left, NGC 5473, magnitude 11.4; below M101 is NGC 5477, mag 13.7; and mid-right is NGC 5474 at mag 10.6. As usual, SEDS has excellent info on M101.
Image Details: Acquired April 29/30, 2006, from the HAS site near Columbus, TX, USA, using my usual equipment. 22x4 minute exposures = 88 minutes total, temps ranged from 63 degrees at the start to 59 degrees when the last image was recorded.. I did my usual processing.
The other HAS Pix from 4/29/2006 are here.
Here's my old film image, rather pathetic by comparison:
Above: M101, the Pinwheel galaxy.
About 50 minutes exposure.
Above photo note: Nikon 300mm f2.8 EDIF lens at f2.8. Lens was mounted on my Losmandy G11 mount using the Losmandy "dual saddle" plate & 125mm rings. Tracking with Sbig STV autoguider. Kodak LE 400 print film, Nikon Coolscan IV ED film scanner. The frames above are extreme crops, with the usual processing in Photoshop 6.0. Above: Copyright 2003, Dick Locke. All Rights Reserved. Contact and Image Use Information