Canon A-1 not closing aperture all the way

Discussion in 'Camera Building, Repairs & Modification' started by altim, Oct 17, 2011.

  1. altim

    altim Member

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    I have a Canon A1 that only closes the aperture blades down to around the largest 1/5 of the apertures of the lens, and then stopping it down further does nothing. This is being tested by locking the dof preview button down and using some FL lenses.

    I tried the same lenses on a different A1 body and they stop down all the way. I checked the distance that the aperture lever moves on both the working and the non-working body and they appear to move about the same distance, any ideas what else I could look at?
     
  2. dnjl

    dnjl Member

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    Did you advance the film lever prior to mounting the lens? If not, try dismounting, cocking the shutter and then remounting. Just a thought.
     
  3. altim

    altim Member

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    Hmm interesting...that fixed the problem. Why does this work?
     
  4. John Koehrer

    John Koehrer Subscriber

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    look into the mirror box. there's a small lever on the right hand side.
    cock the camera and trip it and the lever will move a few mm. cock it and trip it with a light pressure on it and it will travel all the way to the bottom.

    It's part of the metering system that tells the electronics what the f stop is.
    It's likely that you changed a lens before this was reset(cocked)
     
  5. altim

    altim Member

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    That is awesome, thanks for the info everyone. I always enjoy learning something new about cameras :smile: