Table of Contents
Pentax SMC 500mm f/4.5
Summary
The SMC Pentax 500mm f/4.5 is a manual-focus super-telephoto prime lens introduced in 1975 and produced through the 1980s, designed for full-frame K-mount film cameras. It was the longest fixed-focal-length lens in the original K-series lineup (excluding mirror lenses), based on the earlier Takumar 500mm f/4.5 design. With a 4-element/4-group optical formula, 10-blade manual diaphragm, and Super Multi-Coating (SMC), it delivers a 5° diagonal field of view on full-frame—ideal for wildlife, sports, and astronomical photography. The lens features a manual aperture ring (no “A” setting), a minimum aperture of f/45, and a minimum focus distance of 10 meters, which can be halved with extension tubes. It uses rear-mounted 52mm drop-in filters, includes a built-in sliding hood, and ships in a dedicated hard case. It weighs a hefty 3370g, measures 126 × 400mm, and includes a tripod collar for stability.
Tech Specs
| Manufacturer | Pentax |
| Series | Prime |
| Model | SMC |
| Focal Length | 500mm |
| Max Aperture | f/4.5 |
| Min Aperture | f/45 |
| Format | Full-Frame |
| Image Circle | - |
| Minimum Focus | 1000cm |
| Focus Rotation | ° |
| Iris Blades | 10 |
| Optical Design | 4/4 |
| Squeeze | none |
| Front Diameter | 126mm |
| Filter Thread | 52mm (rear) |
| Focus/Zoom Rod | none |
| Native Mount | Pentax K |
| Data Protocol | none |
| Length | 400mm |
| Weight | 3370g |
| Body Telescope | - |
| Body Material | - |
| Focus Drive | - |
| Iris Drive | - |
| Zoom Drive | - |
History
Country of Origin:
Release Date: 1975
Launch Price:
Design Revisions: