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  1. #21
    hmzimelka's Avatar
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    Thank you for all the replies. I have been away for the weekend, so i haven't had the chance to check in and reply!


    Quote Originally Posted by Dan Daniel View Post
    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.
    Thank you Dan. I'll definitely go for better test shots. During the week, I don't have much time to do test shots in good light. I'll have to see what I can do over one weekend. It may be that the curvature is better. The mountain slope, which is sharp in the centre, is a good 100 meters away from the camera. The wall can't be more than 25 or 30 meters away. Even that skew light pole is sharper at its base than at the top. Will try and find a flatter target.

    I'll check the rear lens group when I can. At the moment, I have a roll of film in the camera...



    Quote Originally Posted by ic-racer View Post
    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.
    OK, thanks.


    Quote Originally Posted by jochen View Post
    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.
    Interesting. Thanks. It has always been my habit to advance the transport prior to taking my image. Seems like a good habit
    It will be best to give the camera to an expert, however, it's not the easiest option for me right now... I'll do this when I have a friend going to and coming from the USA, but first I'de need to get my other Rollei working (Automat MX EVS). Seems she has gotten herself a new problem. The film advance doesn't stop at the frame numbers when a film is in the camera.



    Quote Originally Posted by sangetsu View Post
    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.
    Interesting. Hopefully I can have it looked at by a qualified repair man. Perhaps I could simply buy a new Rollei. A 2.8E or something reasonably priced.


    Quote Originally Posted by Ian Grant View Post
    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

    Yeah, definitely needs more testing. However, I have seen on some of my images, that even at f/11 or f/16, that the problem can still be seen, but to a lesser degree of course.

  2. #22
    TheFlyingCamera's Avatar
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    A quick fix for the film advance problem on your Automat- put a single layer of cellophane tape on the sensor roller (the one you thread the paper leader under when loading the camera). That should solve it.

  3. #23
    hmzimelka's Avatar
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    Quote Originally Posted by TheFlyingCamera View Post
    A quick fix for the film advance problem on your Automat- put a single layer of cellophane tape on the sensor roller (the one you thread the paper leader under when loading the camera). That should solve it.
    Thanks. I gave that a try, but it didn't work. That click sound the camera makes, which sounds when the film starts under the backing paper, is heard even without the added tape.
    I tried normal thin tape, and also a thicker gaffer tape. The numbers roll through without stopping. Wonder what the problem is. Everything happens in threes... what is next?

  4. #24
    hmzimelka's Avatar
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    So, for those interested, here is the update...

    I found some RPX 400 in the fridge, which, in my opinion, is not a nice film when Rodinal is the only developer around.
    So, the only use it has for me is test film...

    I screwed the front taking lens group outward until the black ring was aligned with the silver ring sitting around it. This is about 0,55mm outward from it's most tightened position.
    I took some shots with bracketed focus to compensate for the change in focus.

    I then shot an image of the same composition but with the front group screwed all the way in.

    Surprisingly, the images taken with the front group screwed outward, showed the best results. The far edges still focused inward compared to the centre, but not nearly as much as with the front group screwed in.

    Bellow are the links to the images. Please note, the tree is not the focus point. I focused for the hills, at infinity. Shot at f/3.5

    Front group screwed out and Front group screwed in
    Last edited by hmzimelka; 05-13-2013 at 04:52 PM. Click to view previous post history.

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