Strange Meter Malfunction & Cause

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I couldn't figure out why my outer bay lenses would sometimes not activate the TTL meter. I called Pentax and they said send in the body for analysis. I decided not to do this. Upon further investigation on my part, I found that the outer bay extension tube would activate the meter but so would my outer bay lense if mounted for vertical shooting. In the face of the bayonet mount there is a pin that locks the lens in place but it also activates the meter. What happened in my case was that the lenses had become worn in that small indent area that accepts the locking pin. When the lens was attached, it would not depress the pin enough to activate the meter. I am in the process of building up that indent area enough so that it will activate my meter. SR

-- Steve Rasmussen (srasmuss@flash.net), April 10, 2000

Answers

Bobby, I first tried putting a spot of glue at the bottom of the indent, covered by a small piece of thin aluminum sheet. This did not work because one has to work under a magnifying glass to get it right. It is just too difficult (for me)to place the metal correctly. So, I had decided to clean out the mess and replace it with epoxy. It has worked so far but is not a long term fix because epoxy is much softer than the metel pin and will eventually wear. It is best to keep the epoxy surface as parallel as possible to the pin face. SR

-- Steve Rasmussen (srasmuss@flash.net), April 12, 2000.

Steve, how will you build up the indented area? Bob

-- Bobby Mahaffey (mahajen@prodigy.net), April 12, 2000.

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