PENTAX HD Pentax-FA 77mm f/1.8 Limited Lens Silver camera lens

Portrait focal length and aperture

The HD Pentax-FA 77mm f/1.8 Limited Lens is a short telephoto prime designed for Pentax K-mount cameras. Its 77mm focal length becomes a 118mm equivalent on APS-C bodies, a classic perspective for portrait and general photography. The fast f/1.8 maximum aperture provides shallow depth of field and strong low-light capability. This silver-finished Limited series lens targets enthusiasts and professionals who value optical character.

Bright aperture with natural bokeh

The f/1.8 aperture delivers bright viewfinder images and allows subject separation with smooth background rendition. A completely round diaphragm maintains circular highlights across the aperture range, contributing to the lens's signature bokeh quality. HD coating improves light transmittance and suppresses flare and ghosting, preserving contrast in backlit scenes. The optical design resolves fine detail and subtle highlight gradations for high-quality output.

Fixed focal length constraints

As a prime lens, it offers a single 77mm angle of view and cannot zoom to reframe distant subjects. The maximum aperture of f/1.8 defines the shallowest depth of field and the brightest exposure setting available. Autofocus is driven by the camera body via a mechanical screw-drive coupling, so focus speed and quietness depend on the camera used. There is no built-in optical stabilisation, so handheld stability relies on technique or in-body shake reduction.