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  1. #11
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    "...assuming the shutter is the typical reversing kind (moves one direction then the other on alternating frames)..."

    Polyglot: a reversing focal plane shutter? I don't believe I've ever seen one. All FP shutters I've dealt with over the past 40 years have opened in only one direction. Open the back on a Leica M, set to 1 second and fire -- you'll see a curtain release (left to right IIRC), then the second shutter release to end the exposure. Advancing the film and cocking the shutter returns both curtains (now closed) to the left side, and it begins again. I've never seen an FP shutter where the two blinds alternate from side to side -- how would you tension the shutter?

    I'm just trying to learn something new...

  2. #12
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    Admittedly I've only looked at modern (electronic) AF 35mm cameras, but they all go in alternating directions. Shutter is closed with both curtains at one side (actually, top or bottom) of the frame and an exposure is made by moving one curtain then the other, leaving the shutter again closed by with the curtains on the opposite side. It then does the opposite for the next frame.

    I've little idea how it works mechanically but see no good reason for it not to be symmetric - there would merely be two tensioning mechanisms and they are activated alternately when winding on.

  3. #13

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    All at high speeds - but I haven't shot it much at low speeds. Always the same side. I noticed that it is much darker on one roll of film than the other, and the dark roll of film gave me some trouble with winding. I loaded it just like I loaded the first roll, and it started off rather tight. By the time I was halfway into the roll, it was very tight to wind. Would that have caused the darkness somehow? I'm not sure what I did that made it so difficult to wind - the first was fine, the second super tight, and now I have a third in it that is winding fine (like the first).

  4. #14
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    The winding issue shouldn't cause uneven lighting across the frame. You can expose film mechanically by stressing it severely (e.g folding) but that wouldn't cause what you've shown above.

    It's entirely possible the shutter in those is like Trask describes and not what I was thinking off, which would mean you get no alternation of darkness from side-to-side in the case of a lazy shutter. Another experiment you can do is to shoot a correctly exposed blank wall at the three highest speeds. If the darkening gets progressively worse at highest speeds, you can be confident it's the shutter.

  5. #15

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    Hello;
    I have a 1000s and shoot b & w thru it. I have never had a roll run tight thru it and if I did, the dark bag would come out and unload the camera. Just taking a guess here but thinking the backing paper was wedged or torn causing the film to ride up against the focal plane shutter causing scratches and slowing the curtain explaining uneven exposure. Next time unload the camera and investigate the cause before running the roll thru, Steven.

  6. #16

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    Quote Originally Posted by polyglot View Post
    Admittedly I've only looked at modern (electronic) AF 35mm cameras, but they all go in alternating directions. Shutter is closed with both curtains at one side (actually, top or bottom) of the frame and an exposure is made by moving one curtain then the other, leaving the shutter again closed by with the curtains on the opposite side. It then does the opposite for the next frame.

    I've little idea how it works mechanically but see no good reason for it not to be symmetric - there would merely be two tensioning mechanisms and they are activated alternately when winding on.

    No AF or manual camera has alternate traveling shutter blades. It's downward from a cocked condition
    Electronics control the shutter speeds, not the direction of travel of the blades.
    Each set does have a slightly different appearance but only travel in one direction.
    Heavily sedated for your protection.

  7. #17

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    Use a piece of cardboard.

    To see if the shutter curtain is hanging up, take a piece of cardboard like from a cereal box and block off a 1mm strip of the opening on one side of where the film goes. Then do the white test the others are talking about. You should see light when the shutter is released. Then try it a little further across but you will have to either use two pieces of cardboard or cut a slit (1mm) in the one you used. Then try that at the other end of the opening. In other words, try blocking off all of it except the left side, the middle and the right side. If you are seeing light at the 500 and 1000 speed then it is not the camera. If it is, that could mean it is time for a cleaning of the camera. Ric.

  8. #18

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    Should have mentioned this earlier.
    A graduated edge is a typical indication of curtain tension being out of balance.
    On a K1000 the curtain speed(not shutter speed) is 12.5ms. each curtain is individually adjustable and should be close in value
    ~12.3-12.7ms
    The curtain speeds not agreeing will give this type of result and the effect is greater at higher shutter speeds.
    Heavily sedated for your protection.

  9. #19

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    Thank you all for these intelligent replies. I actually discovered that I purchased it with a warranty, so I sent it back for repair/replacement. Here's hoping the next one has a well-behaved shutter.

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