Thursday, September 20, 2012

The Automat

Rolleiflex Automat rear view with VF opened
(Note Exposure Calculation chart on back)

Crank Side View showing the "Automat" frame counter window

I'll probably blog this to death before I actually get to see any pictures I took with it, but today I bought a roll of Ilford FP4 ASA 125 Black and White film, and actually took two pictures - only ten to go now I also discovered what is "automatic" about this camera. You have to cast your mind back to 1951, when this model was introduced. You also have to consider the German precision of manufacturing which they had attained - then it all makes sense. The automatic part is in the loading and transport of the film. This is a totally manual, and mechanical camera, which has no electronics whatsoever, and no battery. It also uses 120 roll film, and for those who may be too young to know about this, "roll film" is a bit different from film concealed within a plastic cannister, like typical 35mm film. 

With less sophisticated roll film cameras, there is a little round window on the back through which you can see what exposure number the film is rolled to, as typically these cameras had no mechanical film counter. The frame numbers were printed in large black letters on the back of the roll, and visible through the round port-hole, usually red plastic. What Rollei did was apply extreme precision "automation" to this film loading and advance process. The Automat has no round red window through which to read the frame numbers - instead, it does have a mechanical frame counter next to the film advance crank. The really amazing part is how the camera "automatically" knows when to start at Frame #1, and then keep counting frames with great precision - remember, this was 1951!. 

The way it was achieved is that when you first load the roll of film, you have to pass the paper backing which "leads" the film through two chromed rollers inside the chamber, and at the point where the actual film starts, these rollers are sensitive enough to detect the change in thickness, and this triggers a little mechanical sensor inside which tells the film advance gears that "Frame #1 is coming up". At that point, the action of the crank changes, so that it locks into position, advances the film counter from 0 to 1, sets the self timer button and cocks the shutter mechanism, all in one drift! Remarkable how this roller mechanism had the precision to measure this difference in thickness, and even more remarkable that it still works flawlessly over 60 years later.

Amazing design for the time, and characteristic of this fine camera.

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