prime35mmdiscontinued
SMC Pentax-A 20mm f/2.8
Pentax · 1984-1996
Ultra-wide for the A-series. Good correction for its era.
Known for
- Architecture
- Landscapes
- Interiors
Considerations
- Some distortion
- Large filter size
Optical Characteristics
Sharpness (wide)4/5
Sharpness (stopped)5/5
Contrast4/5
Flare Resistance4/5
CA Control3/5
Vignetting Control3/5
Distortion Control3/5
Common Issues
- Check for fungus
- Inspect aperture blades
Buying Guide
Specifications
MountPentax K
Focal Length20mm
Max Aperturef/2.8
Min Aperturef/22
Aperture Blades8
Filter Size67mm
Weight250g
Optical Design
FormulaRetrofocus
Elements11
Groups10
CoatingSMC (Pentax)
Pricing
£180 - £300
Typical used price
Mint: ~£400
Adapts To
Sony EFujifilm XCanon RFMicro Four Thirds
Find This Lens
Last verified: Jan 2026Report an error