The SMC Pentax-DA 50mm f/1.8 lens is a normal prime lens for the Pentax K-mount. The 75mm equivalent focal length on APS-C cameras and fast f/1.8 aperture make it well suited for portrait photography. It uses a simple double-Gauss design of 6 elements in 5 groups.

SMC Pentax-DA 50mm f/1.8
MakerPentax
Technical data
TypePrime
Focal length50mm
Focal length (35mm equiv.)75mm
Crop factor1.0
Aperture (max/min)f/1.8 / f/22
Close focus distance0.45 metres (1.5 ft)
Max. magnification0.15x
Diaphragm blades7, rounded
Construction6 elements in 5 groups
Features
ApplicationNormal prime
Physical
Max. length38.5 millimetres (1.52 in)
Diameter63.0 millimetres (2.48 in)
Weight122 grams (4.3 oz)
Filter diameter52mm
Accessories
Lens hoodRH-RA 52mm
CaseS70-70
Angle of view
Diagonal46° (full frame)
31.5° (APS-C)
History
Introduction2012
Retail info
MSRP$249.95 USD

Similar lenses from other manufacturers include the Canon EF 50mm f/1.8 II and Nikon AF Nikkor 50 mm f/1.8D.

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