M81, M82, NGC 3077, and Integrated Flux Nebula

1100mm/F7.3 telescope
Pentax 645z, Nikon D800 (both astro-modified)
Apogee F16M cooled CCD
exposure time: 17.2 hr on the DSLRs and 6.9 hr on the CCD
more details in <a href="http://www.astrobin.com/282932/" rel="noreferrer nofollow">www.astrobin.com/282932/</a>