Table of Contents
Pentax-M SMC 135mm f/3.5
Summary
The SMC Pentax-M 135mm f/3.5 is a compact manual-focus telephoto prime lens for Pentax K-mount 35mm and full-frame digital SLRs, produced from 1977 to 1986. It features a 5-element/5-group optical design, an 8-blade automatic diaphragm, and Pentax’s Super Multi-Coating (SMC) for improved contrast and flare resistance. With a minimum focus distance of 1.5m and a maximum magnification of 0.11×, it’s well-suited for portraits, nature, and compressed-perspective scenes. The lens includes a built-in retractable hood, a 49mm filter thread, and weighs just 270g in a compact 63 × 66mm all-metal barrel. Its long, smooth focus throw (~270°) allows for precise manual focusing, and it delivers excellent sharpness and color rendering—especially from f/5.6 to f/11. Though often overshadowed by faster or more expensive 135mm lenses, the Pentax-M 135mm f/3.5 is praised for its portability, build quality, and value, making it a favorite among vintage lens enthusiasts and a great match for lightweight shooting kits.
Tech Specs
| Manufacturer | Pentax |
| Series | M Series Prime |
| Model | SMC |
| Focal Length | 135mm |
| Max Aperture | f/3.5 |
| Min Aperture | f/32 |
| Format | Full-Frame |
| Image Circle | - |
| Minimum Focus | 150cm |
| Focus Rotation | ° |
| Iris Blades | 8 |
| Optical Design | 5/5 |
| Squeeze | none |
| Front Diameter | 63mm |
| Filter Thread | 49mm |
| Focus/Zoom Rod | none |
| Native Mount | Pentax K |
| Data Protocol | none |
| Length | 66mm |
| Weight | 270g |
| Body Telescope | - |
| Body Material | - |
| Focus Drive | - |
| Iris Drive | - |
| Zoom Drive | - |
History
Country of Origin:
Release Date: 1977
Launch Price:
Design Revisions: