Crown shutter

The Crown are Japanese leaf shutters made by Molta Shōkai, then Chiyoda Kōgaku Seikō (the predecessors of Minolta), in the 1930s and early 1940s. They exist in many models and in three different sizes.

Crown in #0 size

The Crown first appeared as an everset shutter in #0 size, successor of the Lidex. Three versions were made, differing by the range of speeds and by the presence or absence of a self-timer. On all three, the release lever is at the top left (as seen from the front). The early shutter plate is all black, with the name CROWN engraved at the bottom, the words Patents(J.N.)–Pending then Patents–Nippon engraved at the top, and an MTS logo on the right. The late shutter plate has three metal stripes on each side, the words PATENTS–NIPPON in capital letters at the top and no MTS logo; the name CROWN is now inscribed on a larger aperture scale screwed to the bottom.

The Crown A, mounted on the Minolta and Auto Minolta, gives T, B, 1, 2, 5, 10, 25, 50, 100, 200 speeds and has no self-timer.

Crown A on the Auto Minolta. Left: old shutter plate. Picture by S. Montagna. (Image rights) Right: new shutter plate. Picture by A. Apra. (Image rights)

The Crown B has a slightly reduced speed range, omitting the 1s and 1/2s settings, and the Crown S is similar with an added self-timer. They were mounted on the Happy and on the Minolta Six; the latter always has the newer shutter plate.

Crown B on the Happy. Left: old shutter plate. Right: new shutter plate. Pictures by eBayer hbpartner. (Image rights)

The Crown C is a simplified version giving T, B, 25, 50, 100, 150 speeds, only mounted on the Minolta Six and only known with the newer shutter plate.

Crown shutter on the Minolta Six. From left to right: Crown C, Crown B and Crown S. Pictures by eBayer hbpartner. (Image rights)

Crown in #00 size

The Crown shutter was released in #00 size for the Semi Minolta.

The Crown E

The Crown E was mounted on the original Semi Minolta. It is everset, with the release lever at the top left (as seen from the front), and has a small disc acting as an exposure counter. This disc advances each time the release is tripped and it can be manually reset. It is graduated from 1 to 8 with an intermediate stop between two consecutive numbers so that each number is used twice, as it appears in the red windows. The disc makes two full turns during the 16 exposures and each numbered position is shared by two numbers: 5/1, 6/2, 7/3 and 8/4. The patent for this device was filed on April 16, 1934 and published on October 13 of the same year.

Crown E on the original Semi Minolta. Left: 1/100 top speed, early shutter plate. Right: 1/200 top speed, late shutter plate. Pictures by eBayer hbpartner. (Image rights)

The Crown E exists in two versions: the early one gives T, B, 5, 10, 25, 50, 100 speeds, and the late one adding 1/200 top speed. The shutter plate evolved the same as on the #0 size models: all the examples with 1/100 top speed and most examples with 1/200 top speed have a black shutter plate, engraved Patents–Nippon at the top and CROWN at the bottom, and having an MTS logo on the right. The late examples with 1/200 top speed have a newer shutter plate with three metal stripes on each side, the words PATENT–NIPPON at the top and CROWN at the bottom in block letters, and no MTS logo.

The Crown B

The Crown B in #00 size was mounted on the Semi Minolta II. The release lever has moved to the bottom left, to fit the body release mechanism, and the exposure counter disc has been removed; the range of speeds (T, B, 5–200) and the design of the shutter plate are the same as on the late Crown E. The Crown B in #00 size only exists with the newer shutter plate, and the plating of the speed rim switched from nickel to chromium at some time. The very late examples are not everset any more, and have a cocking lever added to the top left.

Crown B on the Semi Minolta II. Left: everset, nickel plated. Middle: everset, chrome plated. Pictures by eBayer hbpartner. (Image rights) Right: with cocking lever. Picture by Jamie Bushley from www.virtualcameramuseum.com. (Image rights)

The Crown II

The Crown II is a newer model developed in #00 size for the Minoltaflex and Minoltaflex Automat TLR models. The earliest examples have T, B, 1, 2, 5, 10, 25, 50, 100, 300 speeds, but the regular version has no T setting. The shutter unit is turned 90 degrees on the TLR cameras, and the speed index is pointing to the left. The shutter plate has three metal stripes above and below the lens; the name CROWNⅡ–TIYOKO is inscribed on a small plate screwed to the left, and the aperture scale is on another plate attached to the right. The release lever is linked to a body release on both TLR models. There is an external cocking lever at the bottom on the original Minoltaflex, also acting as a secondary shutter release, whereas the cocking mechanism is coupled to the film advance on the Minoltaflex Automat.

Crown II (B, 1–300). Left: on the original Minoltaflex. Right: on the Minoltaflex Automat. Pictures by eBayer hbpartner. (Image rights)

Other versions

To be continued.

List of cameras equipped (not exhaustive, and not implying that all the versions have a Crown shutter):

• Semi Minolta II
• Auto Semi Minolta
• Minolta Six

Bibliography

• "Kokusan shashinki no genjōchōsa" (国産写真機ノ現状調査, Inquiry into Japanese cameras), listing Japanese camera production as of April 1943. Reproduced in Supuringu kamera de ikou: Zen 69 kishu no shōkai to tsukaikata (スプリングカメラでいこう: 全69機種の紹介と使い方, Let's try spring cameras: Presentation and use of 69 machines). Tokyo: Shashinkogyo Syuppan-sha, 2004. ISBN 4-87956-072-3. Pp.180–7. Shutter items 18-V-15, 18-Q-6, 24-R-1 and 30-R-1.
• Tanimura Yoshihiko (谷村吉彦). "Semi Minolta I-gata gaibun." (セミミノルタⅠ型外聞, "Things heard about the Semi Minolta I") In Camera Collectors' News no.131 (May 1988). Nishinomiya: Camera Collectors News-sha.
• Tanimura Yoshihiko (谷村吉彦). "Supuringu kamera <semi minoruta>" (スプリングカメラ<セミミノルタ>, "Semi Minolta" self-erecting camera). 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.19–24.