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  1. #11

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    okay here is a rough scan - does this look like flare to you guys? The fogged region is wider than the lens image on both sides and extends below, but it is clearly more prominent in the upper right hand corner of the image.

    Click image for larger version. 

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  2. #12
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    Very nice shot. I see the problem now in the neg and pos images. I agree with Polyglot that this appears to be flare from the sun. Note how it appears lighter at the top of the frame just where the sunshine would be brightest.

    Take it again of you can. Nice view.

    PE

  3. #13

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    The spurious hazy rectangle is suspiciously about the same size and shape as the film aperture, but is slightly displaced and skewed at an angle.

    I think that you have a problem with the camera. Somehow unintended light is striking the film. I suspect a failure of the light baffle that normally covers the film aperture in the rear of the body when the reflex mirror is in the viewing position.

    Normally it prevents stray light from reaching the film. It looks like light is somehow being reflected off of the rear surface of the out-of-position light baffle and onto the film, creating the hazy rectangle.

    Yes, it resembles flare, but that doesn’t explain the offset rectangle with perfectly straight borders. Light reflected off of the rear of the light baffle might account for what you’ve shown.

    Note the warning about not touching the light baffle on page 8 of the owner’s manual and this warning is repeated on page 16

    http://www.cameramanuals.org/mamiya_...67_pro-s-1.pdf

    It might fail on its own or have been tampered with at some point before you acquired the camera if it was bought used.

    That this doesn’t happen on every frame indicates that the problem is intermittent. Eventually, it might occur more frequently if the problem gets worse.

    Note that the hazy area is strongest at the top of the frame. I believe that the baffle pivots with the mirror. The bottom edge is likely the last part to cover the film aperture. Should the baffle “hang up”, the bottom might remain slightly open.

    Any light between the not-quite-closed baffle and film would be somewhat stronger along the bottom than the top. Since the projected image is inverted on the film, the top of the scene corresponds to the bottom edge of the film. That’s where the hazy rectangle in the photo is strongest tending to support the idea that this might be a failure of the baffle to fully close.
    Last edited by Ian C; 10-27-2012 at 12:00 PM. Click to view previous post history.

  4. #14

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    hmmm. thanks Ian. That explanation is more troubling since it means the camera is malfunctioning, but it seems more likely to me than flare for the reasons you've stated. So far this is the only image where this has happened. I guess I will keep my eye on it and if it happens again I will have to have the camera inspected. This shot is from a large project and I have also been shooting each image in b/w so it will be interesting to see whether there is a problem with the b/w version once I develop that film. Unfortunately the project will probably end up needing to be in colour, and I won't be back to that location for some time, so it's likely a lost image.

  5. #15

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    By clicking onto the link at the bottom of the paragraph we can see a B&W negative with an almost identical hazy rectangle from an RZ67

    http://photo.net/medium-format-photography-forum/00Zlp5

  6. #16
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    Ian, your explanation is better than any I have heard. I am having a problem with your explanation (and all others including mine) in explaining how the "flare" goes outside of the frame area into the border. This area is normally masked completely and would even be protected from light via the method you give. So, I'm not sure. Maybe my mind picture is off. IDK. I have changed my mind twice by reviewing the photos posted here.

    I do have an RZ and had an RB and so I am interested in the explanation.

    PE

  7. #17
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    It looks to me like a combination of flare and a small bit of light piping past the edge of the film gate,
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  8. #18
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    Matt, I agree with this in general, but light piping becomes diffuse with distance and therefore the false image should not be so precise. At least that is how I feel.

    PE

  9. #19
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    As the film is not in contact with the image frame, there must be a point light source, or at least rays that are focused at the film plane to cause sharp borders.
    If the baffle had a leak then whilst handling there would be the effect of diffuse exposure.

  10. #20

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    I am also confused by how light is getting to the part of the film which is behind the back's mask, in this case right to the very edge of the film. Interestingly the foggy area is shaped just like the image itself, with the little notches on the corners being extended as if light is being thrown threw the back mask at an extreme angle (which supports the flare theory I think?).

    In racking my brain about this I do remember that at one point during the shoot (not sure if it was this pic) I did attempt to remove the back before putting the dark slide in - I was working very quickly using two backs (colour and b/w) for every shot and I moved the sliders (they only went part way because of the camera's failsafe) to try and unlock it and pulled a little on the back before realizing that it was not coming off - do you think this could have caused the problem?

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