Fig. 20: Moon entering penumbra half shadow: of the earth. The penumbra is the zone in the earth's shadow where only a part of the sun's disk is visible. The darkness is gradually increasing to the center of the shadow where the whole sun disk is behind the earth. — Nikon D200, William Optics ZenithStar 105mm f/7, ISO 100, 1/60s, Ascona, 4 March 2007, 23:18 MEZ Nikon D200; Δt=1/250 s; ISO 100; 3 March 2006 22:23:24
