Prominent (6×9)

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There is also a 35 mm rangefinder camera called the Prominent, also made by Voigtländer, in the 1950s.


The Prominent is a folding bed, coupled rangefinder camera for eight 6×9cm or sixteen 6×4.5cm exposures on 120 film. It was made by Voigtländer in 1932. It was Voigtländer's first rangefinder camera; the rangefinder is separate from the viewfinder, mounted across the top of the camera (the top when held in portrait orientation, as pictured here). It gives a magnified view. Despite its unusual appearance, the function of the rangefinder is much like that in more familiar coupled-rangefinder cameras, except that both windows of the rangefinder are offset from the eyepiece, and receive the view via angled mirrors. One of these is rotated as the focus control on the camera body is turned. The view in the rangefinder is of a split image, not a superimposed double image.[1].[2] The lens is Voigtländer's own Heliar 105 mm f/4.5 with 5 elements in 3 groups. The shutter is usually a Compur giving speeds 1 - 1/250 second plus 'B' and 'T', with a delayed action, but some examples have the rarer Turbo shutter, with the same range of speeds.[3] The Turbo was Voigtländer's own product. According to McKeown, the launch of the Prominent was delayed by technical problems with the new Turbo shutter.[4]

The camera is unusual in that the focus knob can be adjusted with the camera open or closed. The linkage between the knob, the rangefinder, and the focusing mechanism on the folding bed is the subject of patents, including British Patent GB388997, published in 1933.[5] It involves a chain linkage on the bed, and a coiled spring that takes up the tension if the knob is adjusted while the camera is folded. Some of Voigtländer's other folding cameras of the same time, including the Virtus, have the same facility.

The Prominent was the first camera to have a built-in light meter. It is an extinction meter of an unusual type, the light path through it being right-angled; it allows film speeds 0-30 Scheiner,[6] and exposure times from 60 seconds to 1/500 second.[1][2][7]

The camera weighs 790 g.


Notes

  1. 1.0 1.1 Prominent as a lot in a 2006 auction by Auction Team Breker in Cologne.
  2. 2.0 2.1 Early Photography's page on the Prominent has a small diagram of the rangefinder optics.
  3. Prominent with Turbo shutter sold at the sixteenth Westlicht Photographica Auction 16, on 5 December 2009; several pictures. It sold for 3600 Euro, while one with a Compur in the same sale (cited below) sold for 780 Euro.
  4. McKeown, James M. and Joan C. McKeown's Price Guide to Antique and Classic Cameras, 12th Edition, 2005-2006. USA, Centennial Photo Service, 2004. ISBN 0-931838-40-1 (hardcover). ISBN 0-931838-41-X (softcover). p959.
  5. British Patent GB388997 at Espacenet, the patent search facility of the European Patent Office.
  6. Early Photography gives the Prominent as an example of an extinction meter, and gives a conversion table comparing film speeds in Scheiner, as on the Prominent's meter, to other speed systems. 30 Scheiner is equivalent to ISO 64, and steps in Scheiner are equal to those in DIN, i.e. three steps are a doubling in speed. 20 Scheiner is equivalent to ISO 6, and zero Scheiner is thus an absurdly slow speed, even for 1933.
  7. Prominent, also sold at the sixteenth Westlicht Auction: three colour filters of different density can be seen in the top plate of the meter.


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