Production
1971 – 1975
Country
Japan
Optical
7 elements in 6 groups (Planar type)
Updated
Jul 20, 2026
Pentax SMC Pentax K 50mm f/1.2
Pentax K · 50mm · f/1.2
Compiled from 2 real reviews · AI-assisted · accuracy-checked · Updated 20 Jul 2026
Overview
The SMC Pentax K 50mm f/1.2 is Pentax's fastest 50mm — a rare and desirable lens that represents the peak of their manual focus era. With f/1.2 speed and SMC coating, it delivers a unique combination of light-gathering and optical quality.
Verdict: Pentax's crown jewel 50mm. If you shoot Pentax K mount and want the best, this is it. Rare but worth the hunt.
Optical Character
Bokeh
The bokeh is both smooth and busy, with a swirly, painterly quality, but is negatively affected by chromatic aberration.
Color
Pentax SMC lenses are well known for producing saturated, high contrast images.
Sharpness wide open
The lens is just about usable wide open, but does not perform well in terms of sharpness at its maximum aperture.
Contrast
The lens produces higher contrast images than many vintage alternatives, even wide open.
Community Insights
What people love
- f/1.2 speed
- Beautiful bokeh
- SMC coating
- Rare and collectible
- Pentax build quality
What people dislike
- Expensive
- Rare and hard to find
- Heavy
- f/1.2 DoF is challenging
Compatible Adapters
Real adapters from our shop that fit this lens mount.
Standard · ฿325 · In stock
Standard · ฿325 · In stock
Standard · ฿325 · In stock
Standard · ฿325 · In stock
Standard · ฿540 · In stock
Standard · ฿540 · In stock
Standard · ฿540 · In stock
Standard · ฿540 · In stock
Standard · ฿1,250 · In stock
Standard · ฿890 · Out of stock
Pentax K Lenses to Canon EOS R Mount Camera Adapter
Standard · Out of stock
Pentax K Lenses to Canon EOS Camera Mount Adapter
Standard · Out of stock
Sample Photos
Sources (2)
Vintagelensesforvideo
Curated heritage archive
Pentax's crown jewel 50mm. If you shoot Pentax K mount and want the best, this is it. Rare but worth the hunt.