Lens · prime
Nikkor 20mm f/3.5 AI-S
Nikon · 1981-1984
Discontinued35mm
Uses standard 52mm filters where the f/2.8 requires 62mm. Uses the separate HK-6 hood. Nikkor 20mm f/3.5 AI-S: 11 elements in 8 groups, 7 aperture blades, 0.3m minimum focus, 52mm filter thread, 235g.
- Focal length
- 20mm
- Max aperture
- f/3.5
- Mount
- Nikon F
- Format
- 35mm
- Elements / groups
- 11 / 8
Known for
- Landscape
- Architecture
- Travel
Considerations
- Slower than f/2.8
- Some distortion
- Short production run (1981-84)
Optical characteristics
Silverlog's editorial rating: our own judgement, not measured data.
Sharpness (wide)4, level 4 of 5
Sharpness (stopped)5, level 5 of 5
Contrast4, level 4 of 5
Flare resistance4, level 4 of 5
CA control4, level 4 of 5
Vignetting control3, level 3 of 5
Distortion control3, level 3 of 5
Bokeh: Not relevant at this focal length
Rendering: Sharp, good edge performance
Colour: Neutral
Silverlog's editorial rating, 1 to 5; five is best. Not lab-measured.
Common issues
- Focus helicoid wear
- Focus ring stiffness
Buying guide
Check whether the HK-6 hood is included. The 52mm filter compatibility is a significant advantage over the f/2.8.
Specifications
| Mount | Nikon F |
| Focal Length | 20mm |
| Max Aperture | f/3.5 |
| Min Aperture | f/22 |
| Aperture Blades | 7 |
| Min Focus | 0.3m |
| Filter Size | 52mm |
| Weight | 235g |
Optical design
| Formula | Retrofocus |
| Elements | 11 |
| Groups | 8 |
| Coating | NIC (Nikon) |
Pricing
- Typical used price
- £180 - £280
- Mint
- ~£350
Indicative, no dated source.