Table of Contents
Pentax-A SMC 50mm f/2.8 Macro
Summary
The SMC Pentax-A 50mm f/2.8 Macro is a manual-focus macro prime lens introduced in 1984 and produced until 1988, designed for Pentax KA-mount 35mm and full-frame digital SLRs. It was Pentax’s first macro lens with a faster f/2.8 aperture, offering improved brightness and depth-of-field control over earlier f/4 designs. It features a 6-element/4-group optical formula, a 6-blade automatic diaphragm, and Super Multi-Coating (SMC) for enhanced contrast and flare resistance. The lens delivers 1:2 (half life-size) magnification at a minimum focus distance of 24cm, and can reach 1:1 with extension tubes. It uses a 49mm filter thread, weighs 220g, and measures 63 × 40mm.
Tech Specs
| Manufacturer | Pentax |
| Series | A Series Macro |
| Model | SMC |
| Focal Length | 50mm |
| Max Aperture | f/2.8 |
| Min Aperture | f/22 |
| Format | Full-Frame |
| Image Circle | - |
| Minimum Focus | 24cm |
| Focus Rotation | ° |
| Iris Blades | 6 |
| Optical Design | 6/4 |
| Squeeze | none |
| Front Diameter | 63mm |
| Filter Thread | 49mm |
| Focus/Zoom Rod | none |
| Native Mount | Pentax K |
| Data Protocol | none |
| Length | 40mm |
| Weight | 220g |
| Body Telescope | - |
| Body Material | - |
| Focus Drive | - |
| Iris Drive | - |
| Zoom Drive | - |
History
Country of Origin:
Release Date: 1984
Launch Price:
Design Revisions: