I captured this data on the Leo Triplet back in 2013, but I was bad at processing back then and never really worked with it. I decided to give it a go this weekend and found the result to be quite nice. This is 57 minutes of three minute exposures captured with a QSI 583c through a Televue 127is guided on a Paramount ME. The Leo Triplet are around 35 million lightyears distant with magnitudes between 9.4 and 10.