Alsaflex
Advertisement for the Alsaflex, in Réalités, April 1955. scanned by busy.pochi (Image rights) |
Contents
Alsaflex
The Alsaflex is an innovative and compact SLR camera, made in the early 1950s by Alsaphot.[1] It was designed by Lucien Dodin,[2][3] who also held patents relating to the invention of the split prism and micro-prism focusing aids widely-used in SLR cameras, and to their incorporation in SLR focusing screens. The camera makes images 24 mm square on standard 135 film; a panel in the back of the camera is also removable to allow a single-exposure film-holder to be fitted.
The camera is compact for an SLR, largely because it does not have a pentaprism; the image-forming light is instead reflected by a mirror and two prisms mounted within the camera body, and is finally presented, upright and correct right-to-left, in the viewfinder.
The lens is interchangeable (though both the camera and lenses for it are rare), with a bayonet mount in a lens-plate which can be slid upwards (front rise, for perspective control). The shutter is a metal blade, in the form of a fan; a disc with a large sector cut out, rather like the sector shutter in many box cameras, but giving speeds from 1 to 1/2000 second, plus 'B'. The shutter speed control, on the front of the camera, has slow- and fast-speed dials, concentric and one on top of the other.[1] The shutter is synchronised for bulb and electronic flash (at all speeds, according to the notes at Novacon[3]).
Alsaflex 'Dudragne'
The Dudragne is a special, much simpler model of the Alsaflex, without a horizontal viewfinder eyepiece, made to be used with a retinograph (instrument for examining the retina of the eye) made by Dudragne;[4][5][6] In this model, the image is simply reflected upwards to a vertical viewfinder by a single mirror.[4] All but one of the examples cited is without a lens or lens-plate, and it seems likely that these were not needed to use the camera with the retinograph. The shutter has only one instantaneous shutter speed.
Notes
- ↑ 1.0 1.1 Alsaflex serial no. 176, with Boyer Saphir 40 mm f/3.5 lens, sold at the 24th Westlicht Photographica Auction, on 23 November 2013; several excellent pictures of the camera. The camera's shutter speed control is marked to 1/2000 second. An SOM Berthiot Flor 50 mm f/2.8 with the Alsaflex bayonet mount was also sold at the same auction.
- ↑ Alsaflex at Sylvain Halgand's Collection Appareils.
- ↑ 3.0 3.1 Alsaflex at Novacon.
- ↑ 4.0 4.1 Alsaflex 'Dudragne' serial no 414756, at Collection Appareils; the notes state that the last two digits of the serial number give the year of manufacture.
- ↑ Alsaflex 'Dudragne' serial no. 410256,0, sold with Boyer Saphir 50 mm f/2.8 lens, sold at the ninth Westlicht auction, in May 2006.
- ↑ Alsaflex 'Dudragne' serial no. 440 55, sold at the auction Photographica 20 mit Fernoptik + Wissenschaftlichen Instrumenten (Photographica 20 with tele-lenses and scientific instruments) (archived) on 27 May 2012, by Rahn AG.
Links
- Alsaphot page at Gérard Langlois' site, with a link to a picture of the Alsaflex