This is my second attempt at M81 - better than my first I think (http://forum.orpington-astronomy.org.uk/index.php?topic=4232.0)
44x5min. Modified Canon EOS350D on Celestron C11 with F6.3 focal reducer and CLS filter. 2x2 binned in software and cropped.
Main differences:
1) A slightly smaller reducer to focal plane distance has reduced the amount of coma. It's still not quite right - I'm waiting for some adjuster rings to be delivered.
2) The seeing was better - this has increased the sharpness slightly
3) It was a few degrees colder, so less thermal noise.
4) I shot 44 frames instead of 30
(http://gallery.orpington-astronomy.org.uk/albums/userpics/10046/normal_m81_130109.jpg)
Full size here: http://gallery.orpington-astronomy.org.uk/albums/userpics/10046/m81_130109.jpg
I really want to do this (yet again!) but this time somewhere dark e.g. DSC. Let's hope the weather obliges.
Mark
Looks very good to me Mark, an excellent processing job too. As you say a DSC outing would help a lot with the contrast and hence also the core.
Very nice Mark.
Lovely Mark. I would not have thought of doing this with DSLR.
I did 1x480 of Rosette thursday, with Canon, but that was it. Extremely good sky if the clouds hadn't kept appearing. Really a lot of vignetting with 0.6 fr & ED80.
very nice. :D
Mark - That is a fantastic result - you have also got a hint of UGC 5336 (directly at 6pm position below m81 on edge of frame) - This is also known as Holmberg_IX.
http://en.wikipedia.org/wiki/Holmberg_IX
Look forward to seeing you add more from a dark site.
John
Nice one Mark.