Fig.3 - The moon through an 8-inch f/5 Teleskop-Service ONTC Newtonian reflector on an equatorial platform on December 17, 2020. Nikon D7500 (h-alpha modified camera), 1/100 s at ISO 200. A TeleVue Paracorr x1.15 coma corrector was used, leading to an effective aperture of f/5.75 and a total focal length of 1150 mm.