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Studio1476
Tinkerer Username: Studio1476
Post Number: 5 Registered: 06-2008
Rating: N/A Votes: 0 (Vote!) | Posted on Tuesday, March 31, 2009 - 07:04 pm: |
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The aperture indicator scale in the viewfinder of my 137 MA is off, shifted a bit to the left, so that it's reading about a half stop wider than the actual setting on the lens. I've looked under the front panels hoping to find an adjustment point, but haven't seen anything that seems to adjust the zero point for the aperture indicator scale. Anyone have an idea how this adjustment is accessed? |
Studio1476
Tinkerer Username: Studio1476
Post Number: 6 Registered: 06-2008
Rating: N/A Votes: 0 (Vote!) | Posted on Thursday, April 09, 2009 - 10:42 pm: |
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Just in case anyone else should have the same issue with their 137 MA: Taking a second look under the top cover, I found the adjustment point. It's a string-driven pulley that's friction-coupled to and concentric with the aperture indicator wheel. The aperture sensing mechanism in the lens mount couples to the other end of the string. The pulley is right behind the spot where the "X" in CONTAX appears on the nameplate. Stopping down an attached lens to f16 or so will bring the pulley around to the point where the nylon cord is simply glued on to the pulley. (This works OK since the pulley rotates less than a full turn.) The pulley must be tweaked a bit to rotate it a few degrees in whichever direction brings it into proper alignment so that the indication matches the set aperture (use a micro screwdriver blade in the slots on the face of the pulley). Then, re-attach the string with just enough glue to lock the adjustment. Seems to work fine, with the displayed apertures matching the actual aperture settings on the lens. Not that this adjustment is even necessary for the rest of the camera to function, but it's better than seeing a slightly off indication whenever you look through finder. |
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