Pentax 31mm f/1.8 SMC FA AL Limited Autofocus Lens for K-Mount, Black Review

The Pentax 31mm f/1.8 SMC FA AL Limited is a compact wide-angle prime lens designed for Pentax K-mount cameras. Part of Pentax's celebrated Limited series, it combines a fast f/1.8 maximum aperture with an aluminum body and high-quality Super Multi-Coating optics. The 31mm focal length (roughly 47mm equivalent on APS-C bodies) offers a mild wide-angle perspective that suits street photography, environmental portraits, and general walkaround shooting. Its compact form factor and metal construction give it a premium feel, and the Limited series is known for strong build quality and good optical performance. At $560, it sits at the upper end of the prime lens market, especially for a 31mm focal length. The lens is aimed squarely at Pentax K-mount shooters who value a fast, well-built prime with character, though its price and niche focal length may limit broader appeal.