Mini Messier Marathon: M13, M92, M22, M57

I had an exceptionally clear night here in Indiana, and I was able to shoot 4 deep sky objects, plus dark and bias frames all in one 4GB memory card. Here are the results of my Mini Messier Marathon! I've got M13 the Great Globular Cluster in Hercules, M92 another globular cluster in Hercules, M22 a globular cluster in Sagittarius, and a very tiny very faint M57 Ring Nebula at the edge of my imaging abilities!

M13, Great Globular Cluster in Hercules
Total exposure time 1min34s; 94 subs, 62 darks, 45 bias
1.3 sec, ISO 1600, 300mm, f/5.6

M22, Globular cluster in Sagittarius
Total exposure time 1min36s; 96 subs, 62 darks, 45 bias
1.3 sec, ISO 1600, 300mm, f/5.6

M57, The Ring Nebula
Total exposure time 3min; 180 subs, 62 darks, 45 bias
1.3 sec, ISO 1600, 300mm, f/5.6

M92, Globular cluster in Hercules
Total exposure time 3min; 180 subs, 62 darks, 45 bias
1.3 sec, ISO 1600, 300mm, f/5.6