Pentax's final Spotmatic — the Spotmatic F, open-aperture TTL, M42 mount, 1973.
The Pentax Spotmatic F, released in 1973, was the last and most refined of the screw-mount Spotmatics, adding open-aperture TTL metering with the matching SMC Takumar lenses. It sat at the top of the Spotmatic family and marked the end of the M42 line before Pentax moved to the K bayonet. It combined the established Spotmatic body with a more convenient metering method.
This is a 35mm film SLR using the M42 screw lens mount, taking universal M42 lenses, with open-aperture metering when used with the correct SMC Takumar lenses. It has a horizontal cloth focal-plane shutter running from 1 second to 1/1000 plus B, and a fixed eye-level pentaprism with an instant-return mirror. Metering is match-needle TTL that reads at full aperture with the right lenses and stop-down with others. There is no automatic mode; the shutter is fully mechanical and fires without a battery, the cell powering only the meter.
The Spotmatic F suits students, travellers, street and documentary photographers who want the most usable metered screw-mount Pentax, since open-aperture metering keeps the finder bright right up to the shot. It handles smoothly and pairs naturally with the SMC Takumar lenses, while still accepting the wider M42 pool in stop-down mode. It is a dependable, capable body and a fitting close to the M42 era.
As an early-1970s body, checks matter. Inspect and expect to replace perished foam light seals and mirror-damper foam. Test the cloth shutter for pinholes, capping and even speeds. The meter was designed for a 1.35V mercury PX625 cell, now banned, so a modern 1.5V replacement can shift readings unless an adapter or recalibration is used. Check the pentaprism for desilvering or foam haze, and test the advance and rewind. Its mechanical shutter still fires with a dead battery.