Pentax Spotmatic F
Asahi launched the original Pentax Spotmatic model in 1964. It was the first widely-available mass-market camera to feature through-the-lens (TTL) light metering (though the Topcon RE Super, which also featured TTL metering, camera out a few months earlier in 1963). The Pentax Spotmatic F, Asahi’s first camera to feature open-aperture TTL metering, appeared in 1973. The Spotmatic F wasn’t quite the final Spotmatic though… later in 1973, Asahi launched the ES (which stood for Electro Spotmatic) which featured a new electronic shutter which was set automatically by the camera (for aperture priority automatic exposure) for the first time.
Pentax had long been famous for the quality of the ‘Takumar’ lenses they sold to go with their Spotmatic range of cameras. These lenses used the M42 screw mount (often referred to as the ‘Pentax screw’ mount as Pentax was the biggest brand to use it). With the launch of the Spotmatic F and the ES they introduced a new modified M42 lens mount with an extra pin to transmit aperture information to the camera. With earlier Takumar lenses the Spotmatic F uses stop-down metering just like earlier Pentax Spotmatics. These lenses where termed SMC Takumar, and also featured Pentax’s latest super-multi coating.
My Pentax Spotmatic F system
Super Takumar 200mm f/4
In addition to the 55mm f/1.8 SMC Takumar that came with my Spotmatic F, I have just this one additional lens. It is the earlier ‘Super Takumar’ type that has the automatic diaphragm pin, but not the extra pin needed for open-aperture metering.