Canon Model 7 - Picture is darker on the right side

Discussion in 'Film and Processing' started by rui_ferreira|1, Oct 13, 2018.

  1. I recently acquired a Canon Model 7 that I am using with an m39 Jupiter-12 lens. The first 2 film rolls I shoot with it just came in and something's wrong:

    Some scans have the right side of the image darker (pictures attached). Most of the images are like that, though in some scans "the darkness" on the right side is more evident than in others. All 3 images are from the same film roll and I've relied on the built-in light meter [that also seems a bit off].

    Is this a shutter problem? Does it have to do with the lens protruding all the way to the back almost kissing the shutter curtain? Is this a problem from the lab?

    Can someone please share some insights?

    Thanks, Rui



  2. AJG


    If I had to guess it would be likely to be a shutter problem rather than a lens issue. It is unlikely that it is a lab issue. I have used both the Jupiter 12 and the original 35 mm Biogon from which the Jupiter is copied with a Contax III and they both work fine with no obvious darkening of one side of the film that you are seeing. And my 21 mm Biogon is even closer to the film plane, again with no issues.
  3. SCL


    Most issues of this type are shutter curtain problems where the slit width or acceleration/deceleration need to be adjusted.
  4. Sometimes it is enough just to give the camera shutter some exercise before loading and shooting. Run through all the speeds.

    The shutter can drag from accumulated grunge in the shutter channel, a little brushing of that may also help.

    However, such actions are likely to only cure the problem temporarily. Have some body check the shutter.
  5. paul ron

    paul ron NYC


    google "pc diy shutter testers" n try testing the shutter?

    it could be a curtain draging. sitting the camwra in the sun to heat it up, then run it through its speeds may free it up as well.
  6. Maybe I just can't quite see the issue. Have you put your negatives on a light box with a magnifier to see if there is any actual difference between the densities of the negative and the scan (though again I'm not quite sure I see the problem). On the other hand, if you have never serviced the camera, getting someone to clean and check it is a good idea. You might end up with a much more useable camera. The Canon 7 was a great camera, outcompeted only by the Leica M's.

    Something else you can do is to use a spot meter on the various parts of the frame before shooting so you can see if the light reflected from the mountain or building are just lower than the other parts of the picture. Depending on the film, you might just not have that much latitude. Slides have almost NO lattitude, maybe 1/2 a stop for optimal results.

    You could also try sending your negatives to someone with a high quality scanner and see if there are any differences in the scans.
  7. Shutter. Typically happens at higher shutter speeds. The lighting in the examples suggests higher speeds, faster than 1/125, may have been used.
    paul ron likes this.
  8. Google "Shutter Capping." Usually happening at 1/500 and 1/1000 for focal plane shutters. Try exercising the shutter from 1/125 and up; I did my Canon FTB about 50 times at each speed and it loosened up and I haven't seen the problem since.
    Wilmarco Imaging and paul ron like this.
  9. Yes, you should have less problems at intermediate shutter speeds.

    That was likely always true, but especially in aged cameras.

    When I get a new (to me) camera, I estimate the time at 1 second,
    then estimate that successive times to about 1/30 sound about twice
    as fast. Make sure that the shutter actually opens at the highest
    speeds, but try not to use them.

    You could get a CLA, and it might even be worth doing.
    But you might also find that it works well enough between
    about 1/15 and 1/125 for ordinary use.
    Wilmarco Imaging likes this.

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