Lens · prime
SMC Pentax-M 120mm f/2.8
Pentax · 1977-1985
Vintage35mm
SMC Pentax-M 120mm f/2.8: 5 elements in 5 groups, 8 aperture blades, 1.2m minimum focus, 49mm filter thread, 270g.
- Focal length
- 120mm
- Max aperture
- f/2.8
- Mount
- Pentax K
- Format
- 35mm
- Elements / groups
- 5 / 5
Known for
- Portraits
- Headshots
- Events
Considerations
- Uncommon focal length
- f/2.8 limits low light
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
Contrast5, level 5 of 5
Flare resistance5, level 5 of 5
CA control4, level 4 of 5
Vignetting control4, level 4 of 5
Distortion control5, level 5 of 5
Bokeh: Beautiful 8-blade bokeh
Rendering: Excellent compression
Colour: Neutral, accurate
Silverlog's editorial rating, 1 to 5; five is best. Not lab-measured.
Common issues
- Focus ring stiffness
- Less common than 85mm/135mm
Buying guide
Check focus smoothness.
Specifications
| Mount | Pentax K |
| Focal Length | 120mm |
| Max Aperture | f/2.8 |
| Min Aperture | f/32 |
| Aperture Blades | 8 |
| Min Focus | 1.2m |
| Filter Size | 49mm |
| Weight | 270g |
Optical design
| Formula | Telephoto |
| Elements | 5 |
| Groups | 5 |
| Coating | SMC (Pentax) |
Pricing
- Typical used price
- £80 - £150
- Mint
- ~£200
Indicative, no dated source.