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SMC Pentax-M 50mm f/1.4

Pentax · 1977-1984

Pentax's fast standard lens in the compact M series. The f/1.4 aperture provides excellent low-light capability and subject separation. Superb build quality with smooth focus operation.

Known for

  • Low light photography
  • Portraits
  • Available light
  • Creative bokeh

Considerations

  • Some vignetting wide open
  • Softer corners at f/1.4

Optical Characteristics

Sharpness (wide)
4/5
Sharpness (stopped)
5/5
Contrast
5/5
Flare Resistance
5/5
CA Control
4/5
Vignetting Control
3/5
Distortion Control
5/5

Bokeh: Smooth with 8 blades

Rendering: Classic fast 50 character

Color: Neutral, accurate

Common Issues

  • Focus ring stiffness
  • Sticky aperture blades
  • Oil on blades

Buying Guide

Common and affordable. Check aperture operation carefully. More expensive than f/1.7 but worth it for the extra stop.

Specifications

MountPentax K
Focal Length50mm
Max Aperturef/1.4
Min Aperturef/22
Aperture Blades8
Min Focus0.45m
Filter Size49mm
Weight235g

Optical Design

FormulaDouble Gauss
Elements7
Groups6
CoatingSMC (Pentax)

Pricing

£60 - £120

Typical used price

Mint: ~£160

Good value fast standard

Adapts To

Sony EFujifilm XCanon RFMicro Four Thirds

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