Pentax K2 DMD with 55mm f1.8 lens.
From 1976 to 1980, the K2 DMD was the Pentax top model. This “Data Motor Drive” version of the K2 added the possibilty to use a data back and a motor drive. Furthermore, the aperture value and the application of an exposuere correction factor now both are visible in the viewfinder. A viewfinder curtain ensures correct automatic exposure when no eye is looking through. Last but not least, the K2 DMD was the first Pentax to feature an exposure memory lock.