Pentax 50mm f2 SMC Pentax-A

The SMC Pentax-A 50 mm f/2 is a compact, manual-focus standard prime lens introduced in 1985 and produced until 1998, designed for full-frame K-mount film cameras and fully compatible with modern Pentax DSLRs. Optically, it features a 5-element/5-group design, a 6-blade automatic diaphragm, and Super Multi-Coating (SMC) for improved contrast and flare resistance. The lens focuses down to 45 cm, delivers 0.15× magnification, and uses a 49 mm filter thread. It weighs just 145 g, measures 63 × 31 mm, and includes an “A” setting on the aperture ring, enabling full program and shutter-priority modes on compatible Pentax bodies.