4 mm microprism focusing aid plus 12 mm etched circle indicating the area of the meter centerweighting or the Type A with central 3 mm split image rangefinder plus 12 mm etched circle. Nikkormat FT2 The Nikkormat FT2, manufactured from 1975 to 1977, added a permanently affixed hot shoe to the top of the pentaprism cover, combined the two PC terminals into one and switched the light meter battery to a non-toxic silver cell, one 1.5 V S76 or SR44. ASA adjustment also featured a lock and an easier slider than previous models. The advance lever was more contoured with an added plastic grip. The FT2's viewfinder also switched to Nippon Kogaku's new standard Type K focusing screen with 3 mm split image rangefinder and 1 mm microprism collar focusing aids plus 12 mm etched circle indicating the area of the meter centerweighting. A final small touch was the addition of "+" and "-" symbols on the display of the top meter read-out. The numerous little improvements on the FT2 directly reflected customer suggestions for the FTn. Nikkormat FT3 The Nikkormat FT3, manufactured for only several months in 1977 (but still available new from dealer stock in 1978), had the shortest production run of any Nippon Kogaku SLR. The FT3 was essentially identical to the FT2 except that it supported Nikkor lenses with the Automatic Indexing (AI) feature (introduced 1977). AI Nikkor lenses had an external "meter coupling ridge" cam on the lens aperture ring that pushed on an external "meter coupling lever" on a ring surrounding the FT3's lens mount flange to transfer lens set aperture information. Note that most AF Nikkor autofocusing lenses are also AI types. They will mount and meter properly under manual focus on the FT3. However, Nikon's most recent SLR lenses, the AF Nikkor G and AF Nikkor DX types, are not AI types. They will mount, but will not function properly. The FT3 was little more than a stopgap placeholder, awaiting the release of the first of the completely redesigned Nikon compact F-series SLRs, the all-new Nikon FM, with a more compact chassis, in late 1977. The metering system was considered one of the best on the market at the time, as the Nikkormat FT3 remained a very popular camera with professionals and amateurs alike. The Nikkormat EL-series Nikkormat EL The Nikkormat EL was an all-metal, electromechanically (some solid-state electronics, but mostly springs,