Saturday, September 12, 2020

The Voigtländer Prominent: A System 35mm camera from the early 1950s

 The Voigtländer’s 35mm Prominent camera is a strange beast. Nothing seems “normal” with this


camera with many of its controls in strange locations. But bear with me, for there is a logical explanation as to why Voigtländer placed the controls where it did. The reason being the problems all 35mm camera manufacturers and engineers had to deal with in designing a fully-interchangeable lens camera while using a leaf shutter.

    Vignetting is the fundamental issue. A camera with a focal plane shutter does not have this issue since the opening the shutter creates is as large as the film plane opening itself. However, leaf shutters with their round openings cannot give that same coverage. A leaf shutter must be located somewhere closer to the taking lens in order to intercept the cone of light emerging from the rear of a lens before it had spread wider than the largest shutter opening.
    This would suggest that the optimum location be immediately behind the rear element of a camera’s lens when the cone of light focused by the lens is at its smallest. However, two problems remain. One is that a location ideal for a normal lens might not be ideal for other focal lengths. Two, a focusing mount that moves a lens away from the shutter as close focusing occurs may result in vignetting anyway as the distance increases between the rear of the lens and the shutter.
    This was the dilemma Voigtländer faced in the post-war period when it was apparent to the entire German camera industry that 35mm film was going to be photography’s wave of the future. The company wanted to offer a professional, “system” camera that would compete directly against the post-war Leica IIIf and the new model Contax IIa. While as both these cameras featured focal plane shutters, this was not really an option for Voigtländer. Not only did German patents pretty much preclude such a shutter on other makes of rangefinder cameras, but manufacturing a new type of focal plane shutter in-house promised to be expensive and difficult: witness the problems that Eastman Kodak and Bell-and-Howell had in manufacturing and pricing their premier 35mm cameras.
    But Deckel’s Compur Rapid shutter could serve as an alternative. The Compur Rapid shutter had several benefits: It offered a full range of shutter speeds from one second all the way down to 1/500th of a second. In the new “Synchro-Compur” version, full flash sync for all bulbs and electronic flash was available at all shutter speeds. But, more important, it was available to any camera manufacturer and, with the economics of mass production and standardization, Compur shutters were selling at a cost far lower than an in-house focal plane would have.
    The problem with the Compur shutter available in 1950 was that it was really only designed for between-lens installation where vignetting and opening size were not issues.
    Having decided to go with the Compur shutter, Voigtländer attempted to solve the vignetting problem in several ways. It designed a whole series of lenses that would have smaller rear elements that would offer a light cone that could clear the shutter. It placed the shutter right behind the rear element. Then, most important, it fixed the distance between the rear elements and the shutter by causing the shutter and the lens to move as one unit when focused.

    This need to fix and maintain the distance between the back of a lens and the shutter is what led to the placement of a focusing knob on the body of the camera underneath the rewind knob. Focus the Prominent, and the shutter and the lens move in and out as one unit, the distance

between the lens and the shutter never changing. Problem solved.

    But solving one important problem led to other problems and solutions that are less obvious. Deckel later offered

Synchro Compur shutters specifically for behind-lens work. But these shutters were not available until 1956. So the Prominent used a standard Synchro Compur probably designed for larger format cameras. As a result, advancing the film and cocking the shutter requires a complex mechanical linkage with a prong reaching out to slide the cocking lever over, then retracting. Another lever then must come down on the right to release the shutter when the body release is pressed.


    Placing the focus lever on the left end of the camera body in turn required the reticle to be to the right. Convenient for left-eyed users, but not for the opposite.

    The good things: Construction and finish are superb. The chrome is excellent—on a par with post-war Zeiss Ikon cameras. Loading film is straight-forward and conventional. The advance knob/lever is where one would expect, as is the shutter release. The Ultron 50mm f2 lens that came with my camera produces images that are sharp with pleasant colors, although not as impressive as the Nikkors I have used. The normal lens mounts and unmounts easily and can be twisted on either clockwise or counterclockwise. The clickstops are deep and lettering better than most German cameras of that period. All the lenses take the same size accessories. The shutter is quiet, although not as quiet as an Ambi Silette.
    The bad things: The viewfinder is small, dull and the rangefinder patch difficult to see. Later versions of the Type I added albada lines and the Type II went life-size, but that might have been too little too late since Leica had already solved the viewfinder challenge in 1954. At two pounds with the

smaller Ultron, this is one tall, heavy camera: heavier than most SLRs. Certainly not something you want to hang around your neck all day. The two-stroke advance lever has to travel too far each stroke. But worse, the lever hides the frame counter, so the only way you can check the frame number is either start to cock the camera, or kind of peer around the lever. The shutter release is too low on the camera I have and requires me to hook my finger over the wind knob.
    All-in-all, an interesting camera and a leader in the attempt to solve the challenge of a fully-interchangeable-lens 35mm camera while using a leaf shutter, but I camera I will not reach for when I want to enjoy taking pictures.

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