This lens has a 31mm focal length, which provides a slightly broader angle of view than more conventional 35mm lenses, to expand the possibilities of wide-angle photography.

This lens inherits the proven optics of the smc PENTAX-FA 31mm F1.8AL Limited, and incorporates high-grade optical components — such as glass-molded, aspherical elements and high-refraction, low-dispersion glass elements — to deliver sharp, well-defined images of small subjects, such as the very tips of a bare, leafless tree’s branches in winter.

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To further improve imaging power, it also features a newly applied HD coating to produce clear, crisp images even under demanding conditions, and a completely round-shaped diaphragm to deliver a natural, beautiful bokeh (defocus) effect from open aperture to F3.5.