Tuesday, November 3, 2020

The Karat 36, Agfa's top-of-line 35mm folder.

My Agfa Karats: A journey in discovery, frustration and finally satisfaction (Sorta’). 

 Agfa offered its first Karat in 1936. A small, rounded-body bellows camera with a collapsible lens plate mounted on struts, it took Agfa’s Rapid cassettes for 12 non-rewindable exposures per roll. The series moved to a rangefinder-equipped body after the war, taking on a modern chrome and leather appearance. It gained weight and size in the process but remained a compact, well-finished camera. In 1948, responding to the decline in demand for cameras using the Rapid cassette, Agfa brought out the first of its Karat 36 cameras. Although similar in appearance to the earlier Karats, these used 35mm film in standard magazines, and featured a now essential rewind knob.

Agfa Karat 36, type 3 with Xenon lens

In quality and appearance, the Karat 36s rival the Kodak Retina cameras sold during the same period, offering better features in some ways, not so good in others. All were marketed as Agfa’s highest-quality 35mm camera. Priced at $165, they were also Agfa’s most expensive camera, the equivalent to almost $1500 in 2020 dollars. They came with the same quality optics that the Retinas did: Schneider Xenar or Xenon lenses or Rodenstock Heligons, and later, Agfa brand Solinars and Solagons. Also, like the Retinas, all featured Compur Rapid or Synchro-Rapid shutters except the last, very-different Karat IV. I got interested in the Karat series after working with the Ambi-Silette cameras and liking their features. The compactness of the Karats and their split-mirror rangefinders appealed to me. I located a restored Karat, but found that its bellows leaked. The seller took it back, but I kept looking. Prices typically run-higher than the Ambi Silettes, often over $100, and I tend to go as cheap if I can, so it took some time. Several purchases revealed non-operational shutters and/or frozen helicoids. Repair attempts were unsuccessful. Finally, down to zero Karats, I located a Ansco Karomat 36 with the 50mm f2.8 Karat Xenar lens at a low enough price. I took a chance and got lucky. Everything worked, although the advance lever return was initially stiff and the focus lever difficult to move. 

Ansco sold the Karat 36 in the US

Ansco Karomat & Agfa Karat 36. Same cameras with different labels


Agfa 35mm camera focusing helicoids are notorious for their greenish lubricant that hardens over time and can become like glue. The solution is a complete disassembly of the lens helicoid, flushing out all the old lubricant, cleaning, re-lubricating and re-assemblying. Not fun work. A 

little lighter fluid dropped into the threads from the rear, followed by heat from a blower gun freed the focus enough for day-to-day picture taking. But, even though I now had a working Karat, I was still on the lookout for a Karat in better working condition, particularly one with the faster f2 Xenon lens, or equivalent. In July I finally found one at a price I was willing to pay. The metal work shows some corrosion, but the 50mm f2 Karat Xenon was clean and scratch-free. The shutter operated at all speeds and the focus was smoother than the Karomat’s. 

Agfa mark on Karomat
 

The Ansco label
The Karat top.


 

Only the rangefinder was out of alinement—an easy problem to fix since access to the rangefinder prisms is pretty straight forward. So was I happy? For a while. Shot a roll and the results were pleasing. Two weeks later, while exercising the shutter to help the advance get smoother, the shutter suddenly jammed. This time I sent this Karat off for repairs. It’s back now with a replacement shutter. So, we shall see. 

The most distinguishing characteristics of the Karat 36 is its split-mirror rangefinder and its pull-back advance lever. The nice thing about such a rangefinder is that it does not depend on a superimposed image but uses a split image instead. The result is a clear view plus faster and easier focusing, even in low light. I like it. The pull-back advance lever takes a little getting used to, but operates well enough. Hook a thumb or index finger around the front of the lever and pull back. Why did Agfa go with such an advance? Probably due to the demands of the Rapid cassette. When Agfa went over to the 35mm magazine, it carried over the same advance used in the Karat 12. Here is where I feel the greatest weakness of the Karat lies. Instead of a pair of sprockets for pulling the film out of its magazine, the Karat 36s have only one, set back away from the takeup stool and guarded by a snap-over plate. This means that advancing the film depends almost completely on the takeup spool with the sprocket drive pushing the film forward like it would have using a Rapid cassette. It usually works, but advancing the film requires a hard pull accompanied by discomforting crunching sounds. 

 In operation the Karat is solid and easy to steady, the release firm, the shutter ultra-quiet. Since no cover shields the lens when collapsed, it is wise to carry a lens cap if one wishes to stow the camera in one’s jacket pocket. Like other 50mm Schneider lenses during this period, the Xenon takes 29.5mm filters, or 32mm slip-ons. Focus is down to one meter, but with a slip-on proximeter, you can get down to 18 inches. The film type guide and manually-set, additive frame counter are easier to set than the Silette series. Linkages from the body to the shutter are more robust than the Retina’s and the frame counter does not care if you shoot more than 36 exposures on a roll. The 50mm f2 Xenon is the same lens as the Retina IIa came with. Like so many German 35mm camera from the 1950s, shutter speed and aperture settings have no click stops and are difficult to see. This makes bracketing exposures a slow process. I wish the Karat had strap lugs. The cameras came with cases but today many are missing and invariably the straps are rotten and undependable. Still, it is an easy camera to slip in one’s jacket and just take along for a walk or photo shoot. 

With closeup device

 










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.