TTL Problem?

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Has anyone had a problem with their meter needle going up to the top of the overexposed region when using their 300mm at f/45? This happens when I use 50 or 100 speed film. This shouldn't be beyond the EV range of the TTL meter. Any thoughts? SR

-- Steve Rasmussen (srasmuss@flash.net), April 08, 1999

Answers

I think it is time you got a 67 II with its improved metering. What might cause that would be the star effect from the small aperture hitting on the sensor just right (or just wrong). I tried pointing my 300 set at f45 at a light bulb and saw a nice star in stop-down mode. But none of the three meter modes - spot, center or matrix was affected.

-- Tom Goodrick (tgoodrick@earthlink.net), June 25, 1999.

Hello Steve, I checked my 300mm f4 lens on my ttl metering pentaprism and didn't experience the problem you mentioned. If this is the only lens you own which stops down to f45, perhaps the problem could be caused by a dirty contact in the metering system and could be rectified by having it cleaned, or moving the f stop ring back and forth several times to remove any dirt. electrical contacts can build up a very fine film when not used; more so in areas of atmospheric pollution. That's all I can suggest. Hope it proves helpful

-- Tony Wood (awood@telus.net), March 24, 2000.

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