Table of Contents
Pentax-A SMC 35-70mm f/4
Summary
The SMC Pentax-A 35–70mm f/4 is a manual-focus standard zoom lens for Pentax K-mount 35 mm and full-frame digital SLRs, produced from 1984 to 1985. It features a 7-element/7-group optical design, a 6-blade automatic diaphragm, and Pentax’s Super Multi-Coating (SMC) for improved contrast and flare resistance. Its standout feature is a constant f/4 aperture throughout the zoom range—unusual for a compact zoom of its era. The lens focuses down to 0.25m, offering a surprisingly strong 0.37× magnification, making it handy for close-up work. It uses a 58mm filter thread, weighs 330g, and measures 65 × 80mm. The zoom and focus rings are separate, allowing for precise manual control, and the lens includes an “A” setting on the aperture ring, enabling full Program, Shutter-priority, and Aperture-priority modes on compatible Pentax film and digital bodies.
Tech Specs
| Manufacturer | Pentax |
| Series | A Series Zoom |
| Model | SMC |
| Focal Length | 35-70mm |
| Max Aperture | f/4 |
| Min Aperture | f/22 |
| Format | Full-Frame |
| Image Circle | - |
| Minimum Focus | 25cm |
| Focus Rotation | ° |
| Iris Blades | 6 |
| Optical Design | 7/7 |
| Squeeze | none |
| Front Diameter | 65mm |
| Filter Thread | 58mm |
| Focus/Zoom Rod | none |
| Native Mount | Pentax K |
| Data Protocol | none |
| Length | 80mm |
| Weight | 330g |
| Body Telescope | - |
| Body Material | - |
| Focus Drive | - |
| Iris Drive | - |
| Zoom Drive | - |
History
Country of Origin:
Release Date: 1984
Launch Price:
Design Revisions: