Pentax 100mm f/2.8 SMC A Lens
The Pentax 100mm f/2.8 is a 100mm f/2.8 lens designed for Pentax K mount cameras. Check GearFocus for current availability, with buyer protection on every purchase.
Pentax 100mm f/2.8 SMC A Lens
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Lens Overview — Pentax 100mm f/2.8
Key Features — Pentax 100mm f/2.8
100mm f/2.8 Prime: A fixed telephoto focal length with a fast f/2.8 maximum aperture, giving photographers precise control over depth of field and useful light-gathering capability.
Pentax K Mount: Natively compatible with Pentax K-mount cameras, including both film and digital bodies, and usable on APS-C bodies without vignetting.
Full-Frame Coverage: Designed to cover the full-frame format, making it a valid option for any Pentax K-mount body past or present.
SMC A Series Optics: Super-Multi-Coated glass from Pentax's well-regarded A series, designed to reduce flare and ghosting for cleaner images.
Manual Focus Only: All-manual focus operation suits deliberate shooting styles and photographers who prefer tactile control over autofocus.
Lightweight Build: At 290g, this is a notably compact and light 100mm telephoto prime that is comfortable to carry and handle over long sessions.
Lens Specifications — Pentax 100mm f/2.8
| Spec | Detail |
|---|---|
| Use Cases | Portrait, Macro, Creative Effects |
| Lens Type | Prime |
| Format | Full Frame |
| Zoom/Prime | Prime |
| Focal Length | 100mm |
| Maximum Aperture | f/2.8 |
| Camera System | DSLR |
| Lens Mount | Pentax K |
| Autofocus | No |
| Focus Type | Manual |
| Image Stabilization | None |
| Filter Thread | 49mm |
Description — Pentax 100mm f/2.8
The Pentax 100mm f/2.8 SMC A is a prime telephoto lens designed for the Pentax K mount, offering full-frame coverage and a maximum aperture of f/2.8. It is a manual focus lens with no autofocus capability, catering to photographers who appreciate direct control over their focusing. At a weight of just 290g, it is impressively light for a telephoto prime, reducing fatigue during longer shoots.
The 49mm filter thread makes it easy to pair with a wide range of readily available filters. As a full-frame lens, it delivers complete coverage on both full-frame and APS-C Pentax K-mount bodies. The fixed 100mm focal length places it firmly in telephoto territory, well-suited to subjects where a longer working distance is beneficial.
Whether you're building out a Pentax K-mount kit or looking for a lightweight vintage prime, the SMC A 100mm f/2.8 is a well-specified option backed by Pentax's respected SMC A lineage.
Pros — Pentax 100mm f/2.8
- ✓Fast f/2.8 maximum aperture for effective depth-of-field control
- ✓Lightweight at just 290g, making it easy to handle for extended use
- ✓Full-frame coverage on Pentax K-mount cameras with no vignetting
Cons — Pentax 100mm f/2.8
- ✗Manual focus only — no autofocus support for any shooting scenario
- ✗No image stabilization, which can be a challenge in lower light at slower shutter speeds
- ✗Limited to Pentax K-mount systems, restricting cross-platform use
Videos — Pentax 100mm f/2.8
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