Table of Contents
Pentax-A SMC 50mm f/1.2
Summary
The SMC Pentax-A 50mm f/1.2 is a legendary ultra-fast standard prime lens for Pentax K-mount 35mm and full-frame digital SLRs, produced from 1984 to 2004. It features a 7-element/6-group optical design, a 9-blade automatic diaphragm, and Pentax’s Super Multi-Coating (SMC) for enhanced contrast, color fidelity, and flare resistance. With a blazing f/1.2 maximum aperture, it delivers exceptional low-light performance and dreamy, shallow depth-of-field—making it a favorite for portraiture and artistic photography. The lens focuses down to 0.45m, offers a 0.15× magnification, and uses a 52mm filter thread. It weighs 345g, measures 65 × 49mm, and includes an “A” setting on the aperture ring, enabling full Program, Shutter-priority, and Aperture-priority modes on compatible Pentax bodies. While it lacks autofocus, internal focusing, and weather sealing, it’s built solidly with a metal barrel and smooth manual focus throw—ideal for precise control.
Tech Specs
| Manufacturer | Pentax |
| Series | A Series Prime |
| Model | SMC |
| Focal Length | 50mm |
| Max Aperture | f/1.2 |
| Min Aperture | f/22 |
| Format | Full-Frame |
| Image Circle | - |
| Minimum Focus | 45cm |
| Focus Rotation | ° |
| Iris Blades | 9 |
| Optical Design | 7/6 |
| Squeeze | none |
| Front Diameter | 65mm |
| Filter Thread | 52mm |
| Focus/Zoom Rod | none |
| Native Mount | Pentax K |
| Data Protocol | none |
| Length | 49mm |
| Weight | 345g |
| Body Telescope | - |
| Body Material | - |
| Focus Drive | - |
| Iris Drive | - |
| Zoom Drive | - |
History
Country of Origin:
Release Date: 1984
Launch Price:
Design Revisions: