This large-aperture, single-focus standard lens is the newest model in the acclaimed PENTAX Star (★) series — the lineup boasting the best imaging performance of all PENTAX lenses for use with K-mount digital SLR cameras. The lens delivers the superb imaging power demanded of a new-generation, high-performance Star-series lens, assuring exceptional resolving power from the center to the edges of the image field, even when set to open aperture.

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Thanks to PENTAX-original lens coating technologies — including the latest Aero Bright Coating II assuring exceptionally low reflectance, and the high-grade HD Coating — it produces extra-sharp, high-contrast images free of flare and ghost images. Its dustproof, weather-resistant body also makes it extremely dependable and durable for shooting in demanding outdoor conditions.

USAGE NOTE:
This lens features a KAF4 lens mount compatible with an electromagnetic diaphragm control system. Cameras compatible with this system are K-1 Mark II, K-1, K-3 II, KP, K-70, K-3, K-S2, K-S1 and K-50. For K-1, K-3 II, K-3, K-S2, K-S1 and K-50, the camera’s firmware must be upgraded to the latest version.
If this lens is mounted on a camera without proper firmware upgrade, its diaphragm control mechanism becomes inactive, making it impossible to obtain correct exposure.