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prime35mmvintage

SMC Pentax-M 100mm f/2.8

Pentax · 1977-1984

Pentax's compact short telephoto. The 100mm focal length provides excellent portrait compression. Remarkably small and light for a telephoto lens. Sharp and contrasty.

Known for

  • Portraits
  • Candid photography
  • Events
  • Compact telephoto

Considerations

  • f/2.8 limits low light
  • 1m minimum focus

Optical Characteristics

Sharpness (wide)
4/5
Sharpness (stopped)
5/5
Contrast
5/5
Flare Resistance
5/5
CA Control
4/5
Vignetting Control
4/5
Distortion Control
5/5

Bokeh: Smooth telephoto

Rendering: Sharp, punchy

Color: Neutral

Common Issues

  • Focus ring wear

Buying Guide

Affordable and compact. Check focus smoothness. Excellent value short telephoto.

Specifications

MountPentax K
Focal Length100mm
Max Aperturef/2.8
Min Aperturef/22
Aperture Blades6
Min Focus1m
Filter Size49mm
Weight224g

Optical Design

FormulaTelephoto
Elements5
Groups5
CoatingSMC (Pentax)

Pricing

£50 - £100

Typical used price

Mint: ~£140

Good value telephoto

Adapts To

Sony EFujifilm XCanon RFMicro Four Thirds

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