I took these images on February 8, using a 6 inch f/6 Newtonian and ASI183mm with a green filter and Baader MPCC coma corrector. Both of these images are from individual captures (no blending or mosaics). The first image is a stack of 500 frames of 17ms exposures, and the second image is a stack of 50 frames of 2s exposures. Thus, the two raw exposures are separated by 7 stops of exposure, but it's really about 8 stops because the second shot used a higher gain setting. The Earthshine image was pushed by about +4EV in post, which makes the two images even farther apart, although the tonal curve of the first image was also adjusted so it's difficult to say exactly. Some rough measurements lead me to believe that most regions of the Earthshine image are adjusted about 10-12EV from a "normal" exposure of the sunlit surface of the Moon. The reason I exposed the second shot at +8EV and then pushed it further in post, rather than increasing exposure to begin with, is that the spillover of light from the illuminated side quickly starts to destroy the shot, so it's better to underexpose and then control the processing in post. As the waxing crescent ages, it gets more difficult to obtain decent images because the spillover becomes more intense.
Edited by Tom Glenn, 10 February 2019 - 02:54 AM.