The story
From Nikon (a brand of camera often used by professional photographers) + choir. The brand Nikon, which dates from 1946, is a blend of Japanese 日本光学 (Nippon Kōgaku, “Japan Optical”) (from 日本光学工業株式会社 (Nippon Kōgaku Kōgyō Kabushikigaisha, “Japan Optical Industries Corporation”)) and Ikon, a camera brand owned by Carl Zeiss AG. Piecewise doublet of Nikon chorus.
Etymology from Wiktionary, CC BY-SA 4.0.