Lens Lab
    Nikon Nikkor-O 21 mm f/ 4
    Nikon Nikkor-O 21 mm f/ 4

    Nikon Nikkor-O 21 mm f/ 4

    21mm · f/4

    Overview

    The Nikon Nikkor-O 21mm f/4 is a historic super-wide-angle lens from 1959, originally for rangefinders and adapted for Nikon F/F2 SLRs with mandatory mirror lock-up. Its all-metal build feels rigid yet delicate due to the protruding rear element. Optically, it delivers outstanding color rendering but is soft in the center and prone to uneven exposure at fast shutter speeds. Focusing relies on scale/zone methods, best at f/8–f/16. It suits film shooters with early F/F2 bodies seeking a lightweight, unique wide-angle, but modern alternatives offer better performance at lower cost.