Pentax's first named body — the AP, first eye-level pentaprism Pentax, screw mount, 1957.
The Pentax AP of 1957 was the first camera to carry the Pentax name, marking Asahi Optical's move from the waist-level Asahiflex line to an eye-level design. It introduced a fixed pentaprism and a right-hand rapid-wind lever, establishing the layout that would define SLR ergonomics for decades. It sits at the head of the Pentax-branded screw-mount lineage that ran through the S-series to the Spotmatic.
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 giving a right-way-round image, a major step over the earlier waist-level finders. There is no built-in meter, so exposure is set manually, and the body is fully mechanical, firing without a battery. It also carried the instant-return mirror and a wind-on lever in place of a knob.
The AP appeals to collectors of Pentax history and to photographers who want an early eye-level SLR with a genuinely usable finder. The pentaprism and rapid-wind lever make it far more practical than the Asahiflex bodies, though manual exposure and the age of the camera keep it in careful-use territory. It suits deliberate shooting and those who appreciate a landmark body.
As a late-1950s camera, condition is the main concern. Inspect the cloth shutter for pinholes and even travel, and test the slow speeds for stickiness. There is no meter or battery here. Check the pentaprism and finder for desilvering, haze or fungus, since prism problems are common on cameras of this age. Test the film advance and rewind for smooth movement. Usability rests on pairing it with clean, working screw-mount lenses.