Pentax 100-300mm F/4.5-5.6 SMC FA K Mount Autofocus Lens Review

The Pentax 100-300mm F/4.5-5.6 SMC FA is a budget telephoto zoom designed for Pentax K-mount DSLRs. With a modest maximum aperture and a focal range that covers portraiture through wildlife, it offers solid reach for shooters who need flexibility without spending heavily. At $63 for a used copy in excellent condition, it represents an accessible entry point into telephoto photography for hobbyists and those building out a Pentax kit.

The SMC (Super Multi-Coated) treatment helps control flare and ghosting, and the autofocus motor is reliable if not lightning fast. Build quality is straightforward plastic construction typical of consumer zooms from this era. It's lightweight and easy to carry, though the variable aperture means you'll lose light as you zoom in. Image quality at the long end is acceptable for casual use but may show softness and chromatic aberration under scrutiny. This lens fits shooters who prioritize range and affordability over optical perfection or low-light performance.