This is the second of three images I captured on the evening of 21st June. Gassendi has a diameter of 110 km. Its complex floor is criss-crossed by numerous rilles. The Northern wall is interrupted by the relatively deep Gassendi A (33 km). The two most prominent internal craterlets at 10 o'clock to the central peaks are M (3km) and N (4km). Gassendi intrudes into Mare Humorum. As the basalt is quite dark, a longer exposure is required to get a good histogram, so I captured a large file hoping to get a reasonable number of good frames. South is up. Click thumbnail for detail.
C9.25, 2x TV Powermate, Astronomik 2c Red filter, ZWO ASI290MM. Exposure = 4.685ms, FPS =161, Gain=306 (51%), 12,393 frames, 28% stacked in AS!3.