Pentax 50mm F1.4 comparison: M, FA and DFA


The table below summarizes the specifications for the three lenses.

Lens Name

SMC Pentax-M 50mm F1.4

SMC Pentax-FA 50mm F1.4

HD Pentax-D FA* 50mm F1.4 SDM AW

Optical Formula

7 elements in 6 groups

7 elements in 6 groups 15 elements in 9 groups
Image Circle Full frame full frame Full frame
Auto-Exposure Support No Yes Yes
Construction Metal Plastic Metal
Field of View (diagonal / horizontal) APS-C: 32 ° / 27 °
Full frame: 47 ° / 40 °
Aperture Range F1.4 / F22 F1.4 / F22 F1.4 / F16
Aperture Blades 8 8 9 rounded
Aperture Ring Yes Yes, with A setting No
Max. Magnification 0.15X 0.15X 0.18X
Focus Type Manual Screw-drive SDM, quick-shift
Minimum Focusing Distance 45 cm 45 cm 40cm
Internal Focus  No No Yes
Filter Thread Diameter 49 mm 49 mm 72mm
Cap Plastic clip-on Plastic clip-on Plastic clip-on, O-LC72
Hood None dedicated Accessory, PH-SA49, PH-RA49, RH-RC49 Included, PH-RBB72
Case Dedicated hard case S70-70 Included, S100-140
Diameter x Length 63 x 37 mm 65 x 37 mm 80 x 106 mm
Weight 235 g 220 g 910g (hood: 45g)
Pentax Mount Designation K KAF KAF4
Weather Sealing No No Yes
Price (US MSRP)


$346.95 $1019.31
Launch Date


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