三條月溪清晰易辨

C.L.Chan

澄海東北的大隕坑是波西多尼, 三條月溪清晰易辨. 小圖是月球軌道器拍的, 3 Rimas in Crater Posidonius, UT: 2020/11/22,10h13m, Telescope TEC Maksutov-Cassegrain MC200/20,D=20cm, F.L.=400cm, Losmandy G-11 Equatorial Mount with motor drive. Camera QHY5III 224 Color Cam,  Shoot by FireCaptureat Gamma=100, Gain=41, Expo= 0.4ms/frame, frame rate=20 frames/sec, RGB &avi format, stack and process 40% best frames in 1803 frames,­ with SoftwareAstroStackert 3 with DSR, wavelet with RegiStax V.6,  final touch by GIMP & Microsoft photo.Atmospheric condition: Transparent: 9­/10, Seeing: 9/10, Equipment borrowedfrom Mr. Ng. The photo was taken at Kennedy Town堅尼地城, Hong Kong.