| Author |
Message |
    
Chris
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 01, 2004 - 04:34 am: | 
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I was adjusting my Spotmatic SP meter (BTW, thanks to John Farrell’s advice on how to reach the trimmer), when I noticed wildly different results using different lenses. There were up to 1.5 stops difference!
Conditions:
1. Piece of paper stuck on window, with lens pressed against it (= lens angle not a factor)
2. Outside light constant
3. No meaningful light entering viewfinder and influencing results.
4. The SP has no full-aperture metering provision, so that isn’t an influence.
5. Lens focal length (for whatever reason) not a factor: 17mm & 400mm gave same results.
6. The same lenses on another camera (a Rolleiflexflex SL35-E, using an adaptor) gave results within half a stop of each other (so the problem isn’t the lenses).
What could be going on?
Thanks,
Chris |
Ed
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, April 01, 2004 - 01:08 pm: |
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you're talking widely different focal lengths--bear in mind that all lenses are not equal, especially if you get into cheaper brands and considering that the Spotmatic is stop down metering--you see what you get.
shoot some pics and see how they are. |
Chris
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, April 02, 2004 - 01:24 am: |
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As metioned before, all the different lenses checked out essentially ok on a different camera, still using stop-down metering...
And most of these lenses I've had a long time and used a lot (more than a few pics) on different cameras; the mystery still lies with the Spotmatic.
Chris |
Donald Qualls
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, April 06, 2004 - 08:22 pm: |
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Could your camera be failing to completely stop down the lens? Check (from the front) that the diaphragm is reaching the same diameter on the Spottie that it does on your other camera(s). If that's not the problem, check that you don't have a sticky automatic diaphragm -- I have one on my 135 mm that's slow the first few times I stop it down, and then it seems fine (except that it still overexposes a frame now and then). You might not have trouble on the other cameras because by then the stickiness has worked out. |
