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  1. #11

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    A real cleaning of a shutter involves removing it from the lens board. This allows for thorough cleaning and maintenance.

    Typical removal ofthe lens blocks would involve simply unscrewing the front block en masse and the rear block masse. There is no breakdown of the front or back lens groups needed. Of course this doesn't mean that it didn't happen. Sometimes the front retaining ring, for example, is actually retaining the front lens element, not the front lens block.

    I am not certain about your sample image above- so many sloping surfaces, hard to know what is what. this is where the infamous brick wall shows it usefulness. My first impression is that it doesn't have the curved focal plane of previous shots you showed?

    My thinking is that whoever worked on the shutter removed it from the lens board. this means undoing the retaining ring/tube on the back of the lens, inside the film chamber. Underneath this ring is a washer that look amazingly like the one you show. I bet whoever put the camera back together forget where that washer went, or simply had it left over when he thought he was done. So he put it on the first place it fit- the back of the front lens group. The washer isn't serving any functional purpose on the back of the lens board, it's just your standard 'best practices' approach to tightening down assemblies.

    Try for beter test shots. Try with and without the washer. Let's hope it was what I think, because you will be done shortly if so. But then again, other things such as people have mentioned might be the cause.

    Oh, I haven't even given much attention to the back lens block. You can take a small screwdriver and very lightly see if it can be spun out by putting the screwdriver tip in one of the retaining ring slots. And see if it can be tightened down any. Be very very VERY VERY careful here- metal and glass are a nasty combination if you slip. There are other ways to check this- I save wooden chopsticks from takeout to whittle safer tools for things like this. All you are doing is checking for looseness.
    Last edited by Dan Daniel; 05-02-2013 at 01:41 PM. Click to view previous post history.

  2. #12
    ic-racer's Avatar
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    Quote Originally Posted by hmzimelka View Post
    Do I understand you correctly, that moving the element away from the shutter, that the perimeter will focus further towards infinity while the centre will largely be unchanged? ..
    My error it is the other way around, too late to change my post above.
    In terms of film bulge, on 120 SLRs you can check this with "B" and press the tip of a pencil on the film to see if it indents. You know the film can never bulge backwards behind the pressure plate unless your pressure plate is bent. So even if the film has a curve to it, when it gets squeezed between the film gate and the pressure plate it can only bulge in one direction...toward the lens. I will say that I have not had a camera that did it consistently with all films, so you may have a lens issue as others have pointed out.

  3. #13

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    Hello,
    the Planar/Xenotar was a remarkable improvement of field curvature against the Planar/Xenar. The problem of 120-film of not being flat in the camera is as old as this film. Carl Zeiss made investigations of this problem and found that the best flatness is immediately after transport. The film remains flat for about 15 minutes and than the curvature comes back. So it is best to transport only immediately before the exposure is made. The Rollei service had special non flat matted screens for testing the focus into which the average curvature of film had been grounded. The Rollei service also had exploded views of the lenses and how to center and adjust them. In this views you could see whether and where there should be a washer or not. Testing of focus was made with a so called autocollimator and they had very close specifications for measurement of the alignment of the front plate and the focus.
    The best would be to give the camera to a real expert with appropriate equipment.

  4. #14
    Richard Sintchak (rich815)'s Avatar
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    Quote Originally Posted by jochen View Post
    Hello,
    the Planar/Xenotar was a remarkable improvement of field curvature against the Planar/Xenar.
    Did you mean Tessar/Xenar?
    -----------------------

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  5. #15

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    I think that "washer" was a spacer and probably used to set/achieve infinity focus.

    Depending on the construction of the lens, there might not be a free-standing middle element or group. However, when a middle lens element is placed in the camera backward, the impact on image quality is very obvious. I don't think that is your issue here.

    I have some theories, but without seeing the camera, it's difficult to say whether they might apply to your camera.

  6. #16

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    I have never seen a spacer used to calibrate the lens on a Rolleiflex camera. The washer shown does resemble the washer used between the shutter and the front standard, but the aperture assembly would not work properly and the shutter assembly would be loose if the washer were ommitted. The Xenotar lens does not have many elements, and installing them in the wrong order or in the wrong direction is highly unlikely. Ommitting a spacer between elements would either allow the unspaced element to rattle around, or break when the retaining ring was screwed on. Most likely the front and rear groups are mismatched, and the rear half is from a Planar.

  7. #17
    Ian Grant's Avatar
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    Maybe the spacer was added to optimise the lens for close focussing, seem fine without it. You may also be expecting too much of f5.6

    I wouldn't draw too many conclusions from those images. It needs testing more objectively.

    Ian

  8. #18

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    Quote Originally Posted by sangetsu View Post
    The washer shown does resemble the washer used between the shutter and the front standard, but the aperture assembly would not work properly and the shutter assembly would be loose if the washer were ommitted.
    There is also another washer behind the lens board, between the lens board and the shutter retaining ring/light baffle piece. This is where I think the washer came from. It being left out won't affect any mechanical systems.

  9. #19

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    Sorry, off course I ment the former used 4-lens types Tessar and Xenar. If you increase the distance between the front lens group and the rear lens group by inserting a washer, I think besides poorer image quality and increased aberrations you will get a change in the reproduction scale. It is something like a front lens focussing.

  10. #20
    Ian Grant's Avatar
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    Quote Originally Posted by jochen View Post
    Sorry, off course I ment the former used 4-lens types Tessar and Xenar. If you increase the distance between the front lens group and the rear lens group by inserting a washer, I think besides poorer image quality and increased aberrations you will get a change in the reproduction scale. It is something like a front lens focussing.
    That's correct. More importantly that's introduces distortion when a lens is then used at or near infinity.

    One of the long CZJ Tessars has quite a large spacer like a small extension tube for close up work where its used as a process lens, this needs to be removed for normal work. G-clarons are also optimised this way.

    Ian

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