The Japanese Konishiroku company made a 6×6cm SLR prototype before the early 1950s. The camera is only known from an article by Sakurai Minoru (桜井実) in the September 1951 issue of Photo Art. No picture is provided, and the original text is as follows:
- 一流メーカーで国産一眼レフのないのは真に淋しい限りです。一度小西六で試作されましたが、本機はヘキサー1:2.8 f=80ミリ、シャッターフォーカルT・B・1～1000、シンクロ、セルフ、自動絞り付という高性能なもので、その製造中止は理由の如何を問わず真に残念千万で、何んとかならぬものでしょうか？
The text describes the camera as having a Hexar 80/2.8 with auto diaphragm, a focal-plane shutter (B, 1–1000), flash synchronization and a self-timer. The last sentence says that "the fact that production was abandoned is really a pity, regardless of the circumstances; isn't there something that can be done?" The phrasing seems to imply that the camera was abandoned a few years earlier, maybe even during World War II — in another section of the same article, the author similarly regrets the abandon of the 1937 Olympus Standard.
No other detail is known, and no photograph of the camera has been found so far.
- Sakurai Minoru (桜井實). "Kōkyū kokusan kamera no jōzu na erabikata" (高級国産カメラの上手な選び方, How to choose a high-end Japanese camera). In Photo Art no.27, September 1951. Pp.89–93.