Nikon Flash Speedlight SB-910

Guide Number 34 m/111.5 ft. (at ISO 100, 35mm zoom head position, in FX format, standard illumination pattern, 20°C/68°F) to 48 m/157.5 ft. (at ISO 200, 35mm zoom head position, in FX format, standard illumination pattern, 20°C/68°F) Guide Number34 m/111.5 ft. (at ISO 100, 35mm zoom head position, in FX format, standard illumination pattern, 20°C/68°F) [...]  See More..