CAMERAS > SUMIDA
K.K. Sumida Kōki Seisakusho or Sumida Optical Works was a Japanese camera maker from 1950 to 1953.
"Sumida" is the name of a river in Tokyo, and also of one of the 23 boroughs of the Japanese capital. The company was installed there: its address was Arakawa-ku Minami-Senju 2–13 from 1950 to 1952. From mid-1951, the sales department was installed in Minato-ku Shibasakurada Bizen-cho 12. In 1953 the company had a single address, Setagaya-ku Daita 1–748.
Proud had been the camera manufacturer (that manufactured helicoid focusing rangefinder camera for the first time in Japan in 1937) before the W.W.II. But after the war, the manufacturer changed to Sumida Optics and it had manufactured cameras under the name of Proud since then.
The ancestor of Sumida was the company Proud-sha, founded by Miyazaki Shizuma and apparently merged into Miyoshi Kogaku around 1940. The first cameras made by Sumida were perhaps the Apollo and Mikado folders, a direct continuation of the Roavic by Miyoshi Kogaku, itself descending from the Semi Prux by Proud - and apparently inspired in the Kodak 620 Duo. The Apollo and Mikado are sometimes attributed to Nishida, which provided the lenses and shutters, but this is probably a mistake.
One source says that Sumida was first called "Million Optical", but no further evidence has been found to sustain this - Sumida indeed marketed a camera called Million Proud, where Million is a part of the model name.
Sumida made a number of cameras called Proud, and the sales department was briefly called "Proud-sha" in mid-1951. From 1950 to 1952, the company's logo was formed by the letters KSK, with the "S" vertically elongated to draw some sort of cross. From late 1952 onwards, it used a logo formed by the words KSK Proud inside an oval, with a stylized "P". This logo is very close to the one used by Proud-sha before the war.
Olympus somehow got hold of the rights and continued a Chrome Six line of their own! It's all very confusing, and has presented an historical puzzle for researchers for a long, long time.