Japanese medium-format SLR (edit)
6×9 Rittreck (6×9)
6×8 Fujifilm GX680
Japanese TLR and pseudo TLR ->
Other Japanese 6×6, 4.5×6, 3×4 and 4×4 ->

The Minolta SR66 (ミノルタSR66) is a 6×6 SLR camera made as a prototype by Minolta in 1968.[1]

Concept and public apparitions[]

The design of the SR66 allows for interchangeable lenses and finders, and exchangeable film backs for 120 or 220 film. The camera has an electronically governed metal focal-plane shutter, but none of the sources mentions auto-exposure.[2]

The Minolta SR66 never went into full production, supposedly because Minolta decided to concentrate on 35mm cameras.[3] The camera was perhaps a long way from actual production: the first serial-produced Minolta camera with an electronically governed focal plane shutter was the X-1, only released in 1973. In 1967 or 1968, at the same period as the SR66, Konishiroku showed a prototype auto-exposure SLR in 4.5×6cm format, the Konica SF, which was abandoned too. In 1969, Asahi successfully released the Pentax 6×7 with an electro-mechanical shutter, which became the first serial-produced medium format camera to have such device.

The SR66 camera was not presented to the general public at the time, and the first picture surfaced in 1988 in the Japanese camera collecting magazine Kurashikku Kamera Senka.[4] A surviving prototype has been photographed with a "waist-level" finder and a standard Auto Rokkor-PF 80mm f/2.8 lens (no.1200004). It was displayed at the JCII exhibition about Konica and Minolta in 2005 with an eye-level finder; pictures taken at this event also show three interchangeable lenses (certainly two tele and a wide angle), in addition to the standard lens mounted on the camera.


The Minolta SR66 has a roughly cubic shape with rounded edges, pretty similar to the Hasselblad or to the later Bronica SQ. There is an advance crank on the photographer's right, which can be turned as a knob as well. The main release is at the bottom corner of the front plate and is actuated by the photographer's right fingers; it is surrounded by a lock lever. Another control is visible on the left side of the camera, probably for the shutter speed. The nameplate is in front of the viewfinder, it has the late 1960s minolta logo (same as on the 35mm SR and SR-T models) and the model name SR66 written in black inside a silver square.

The lenses have a black and silver finish. The black focusing ring is engraved in metres (in white) and feet (in green) and has a diamond-point rubber grip (doubled on the tele lenses). The silver-coloured aperture ring is at the back of lens and there is a fixed silver ring with depth-of-field indications in between. The lenses have a silver nose with a bayonet filter attachment. The wide angle lens has a fixed silver or champaign part between the focus ring and the filter attachment. The engraving of the standard lens is MINOLTA LENS MADE IN JAPAN AUTO ROKKOR-PF 1:2.8 f=80mm 1200004, the PF code indicating six elements in five groups. One of the tele lenses perhaps has AUTO TELE ROKKOR-QE 1:3.5, indicating five elements in four groups.[5]

The waist-level viewing hood is plain black and of the four-fold type. The eye-level finder has a long protruding eyepiece on the rear, and its front part has the minolta logo.

The film back has a small crank on the right side, perhaps surrounded by an exposure counter and film reminder. It also has a button at the bottom of the right side, perhaps used to unlock the back and remove it from the camera.


  1. Date: Kurashikku Kamera Senka no.12, p.60.
  2. Konika-Minoruta-ten, p.27, and Shiramatsu, p.25 of Kōkan Classic Camera no.14, have "electronically governed" (電子制御式) and Kurashikku Kamera Senka no.12, p.60, has "electric" (電気式). None mentions auto-exposure.
  3. It is the reason invoked in Kurashikku Kamera Senka no.12 (p.60).
  4. It is said on p.60 of Kurashikku Kamera Senka no.12 that the SR66 was "first presented here" (今回はじめて公表された).
  5. Close observation of a photograph taken at the 2005 exhibition about Konica and Minolta in the JCII museum.


  • Konika-Minoruta-ten (コニカミノルタ展, Konica Minolta exhibition). Exhibition catalogue. Tokyo: JCII Camera Museum, 2005. (P.27)
  • "Minolta Camera: Shisaku kamera" (Minolta Camera: 試作カメラ, Prototype cameras). Kamera Rebyū: Kurashikku Kamera Senka (カメラレビュー クラシックカメラ専科) / Camera Review: All about Historical Cameras no.12, October 1988. No ISBN number. Minoruta kamera no subete (ミノルタカメラのすべて, special issue on Minolta). Pp.60–1.
  • Shiramatsu Shō (白松正). "Minoruta no shisakuki wo miru" (ミノルタの試作機を見る, Looking at the Minolta prototypes). Kōkan Classic Camera no.14. Special issue on Minolta (特集ミノルタ・ロッコール伝説). P.25.


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