There are some beautiful images of this comet on the web. This is not one of them. But I had some time at the end of my sesson on M57 with the 11 inch HD and the comet, just northwest of M15, was at transit so in perfect position for imaging. I did not have enough time for RGB acquisition so I settled for a quick series of unguided 50s luminence exposures. In this image, I aligned the subs on the comet head, and the star streaks show the amount of relative motion over the 1 hour of imaging. There are interruptions in the star streaks because unguided, my mount occasionally fails to track adequately over 50 seconds, so several frames were not used.
My back yard, August 5, 2011, 2 - 3:12 AM, Parsec 8300M on 11 inch HD, 36x50 seconds luminence, unguided.