Pentax's early screw-mount SLR — the K (1958), all-mechanical, not the later K-bayonet, 1958.
The Pentax K of 1958 was an early screw-mount body in the first generation of Pentax SLRs, and should not be confused with the much later K-bayonet system that borrowed the same letter in the 1970s. This camera uses the screw mount throughout. It sits within the S-series family that developed the eye-level pentaprism design first seen on the AP.
This is a 35mm film SLR using the screw lens mount that became the M42 standard, taking Asahi's screw-thread lenses. It has a horizontal cloth focal-plane shutter and a fixed eye-level pentaprism with an instant-return mirror. There is no built-in meter, so exposure is set by hand, and the body is fully mechanical, firing without a battery. It featured a semi-automatic diaphragm arrangement working with the lenses of its day.
This early K suits collectors and photographers who value an all-mechanical Pentax with a clean eye-level finder. It handles simply and directly, though manual exposure means carrying a separate meter or relying on experience. It is a slow, considered camera rather than a quick everyday tool, and it appeals to those tracing the development of the Pentax line.
As a late-1950s camera, condition varies. Check the cloth shutter for pinholes and even travel, and test the slow speeds for stickiness. There is no meter or battery here. Look closely at the pentaprism and finder for desilvering, haze or fungus, a frequent issue on bodies of this age. Test the film advance and rewind for smooth movement. Practicality depends on clean, working screw-mount lenses.