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03-18-2010, 03:28 PM   #1
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645 Issue

Recently picked up the original 645 and the A80-160mm zoom. Shot a roll of Provia to test the system, and the returned slides were so underexposed that they were nearly black; Is this a problem with the system or the user? Its was shot on shutter priority auto mode.

03-18-2010, 04:03 PM   #2
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Just to add, I have checked the iso setting, it was correct.
03-18-2010, 04:59 PM   #3
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Do the aperture blades snap open and closed when you activate them manually? You might notice some darker areas on the blades - leaking lubricant/oil that might be gumming up the works and causing the blades to not open/close properly. Although, if it is underexposed, then that is probably not the issue (when you focus and before you depress the shutter, the blades should be fully open) and I would suspect overexposure might be more likely, but who knows.

The P645 original has an additional battery - large, flat button like - apart from the 6 AAs in the grip. Perhaps this is expired or putting out too little voltage and causing problems?

Also, I can't remember, but I thought the P645 has exposure compensation. Could it be engaged and causing your underexposure? Might also be worth you while to put in some new AA batteries.
03-18-2010, 05:03 PM   #4
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The lens is perfect, hardly used, no problems. Exposure compensation was not engaged, but I'll try out switching the battery. In my opinion it almost looks like the iso was off, even though it was set correctly.

03-18-2010, 08:18 PM   #5
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Now this is perplexing. I compared metering readings to my P5, at at the same aperture, shutter speed and iso, the 645 is off by EXACTLY one stop. i.e. My 100 iso film must be shot at 50. Any ideas what my be causing this? I've got a feeling I'll be replacing it.

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