Kansai Kōgaku (関西光学) was a Japanese optical company that made telescopes and other astronomical devices. It was based in Kyoto. During the war, Kansai Kōgaku was linked to the company Takashimaza Iida K.K. (高島座飯田㈱) and the distributor of the Kanko products was the company Kashimura Yōkō.
Kansai Kōgaku made the Miya Type 2 telescope camera (ミヤ二式反射望遠写真機) at the end of the 1930s or beginning of the 1940s. An original picture of the Miya Type 2 is reproduced in this page of the Old Telescope website but it is impossible to recognize the camera body.
The company later made the 450mm Kanko 2600 (カンコー2600) mirror lens, certainly from 1940 (year 2600 of the Japanese mythological calendar). It was advertised in March 1942 as available for the Leica and Contax mounts and in SLR mount. The advertisement says that the resulting No-lens telescope camera (レンズ無シの望遠写真機) was an improvement of the former Miya Type 2 telescope camera (旧ミヤ二式反射望遠写真機改良方). The advertising picture shows the Kanko 2600 mounted on a Flex Six or Shinkoflex camera body, and surviving examples of this combination are known. One is pictured in Sugiyama and another in this page of the Old Telescope website. The range advertised in March 1942 also comprised the 450mm Kanko I (カンコーⅠ型), the 600mm Kanko II (カンコーⅡ型 ) and the 1,000mm Kanko III (カンコーⅢ型).
- Its address in 1942 was Kyōto, Yamashina (京都山科). Source: Advertisement published in Hōdō Shashin March 1942, reproduced in the Gochamaze website (archived).
- Advertisement reproduced in the Gochamaze website (archived).
- Advertisement published in Hōdō Shashin, reproduced in the Gochamaze website (archived).
- Sugiyama, item 6008, calls the combination "Flex Six (military version)".
- Sugiyama, Kōichi (杉山浩一); Naoi, Hiroaki (直井浩明); Bullock, John R. The Collector's Guide to Japanese Cameras. 国産カメラ図鑑 (Kokusan kamera zukan). Tokyo: Asahi Sonorama, 1985. ISBN 4-257-03187-5. Item 6008.