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M13 Hercules Cluster (5in f6 7D).jpg
M13 with 130mm Astro-Physics apo at f/6 with no field flattener (slight camera tilt results in more coma at left of frame), for stack of 6 x 6 minute exposures at ISO 800 with Canon 7D (stock camera, not modified). Auto-guided with SG4. Worked perfectly. Slight rotation around guide star made it impossible for Photoshop to do an auto-align. Had to manually align.