Equipment category: ,

The Nikon 20mm F/4 Nikkor AI was introduced in 1977 and it was sold until 1978. It’s a super-compact, ultra wide-angle lens. For many years, this lens has been favored by landscape photographers. The 20mm f/4 employs excellent optical quality and accepts 52mm filters.

The 20mm f/4 AI is the smallest ultra wide prime or zoom lens ever made by Nikon. It’s smaller than any 50mm. Its color rendition matches most other multicoated Nikkor lenses, and it has little to no distortion.


Technical Specifications and Features

  • Focal Length: 20mm
  • Camera Mount Type: Nikon F Bayonet
  • Optics: 10 elements in 8 groups
  • Diaphragm / Iris: 7 straight blades – Metal – Full-stop clicks
  • Aperture Maximum: f/22
  • Aperture Minimum: f/4
  • Format Compatibility: Nikon FX/DX/35mm Film
  • Angle of View: 94º on FX / 71º on the smaller DX format
  • Close Focus: 1 Foot (0.3 meter)
  • Hard Infinity Focus Stop: Yes
  • Weight:  7.4 oz. ( 210 grams)
  • Dimensions: 35.5mm (1.4″) diameter x 63.5mm (2.5″) long
  • Hood: HN-14 Screw-in Metal
  • Filter Size: 52mm