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07-28-2013, 11:56 AM   #31
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QuoteOriginally posted by Canada_Rockies Quote
Spot metering with screens with central focus aids has nothing to do with the camera and everything to do with the blackout in the screen.
That may well be a factor, though my K10D has spot metering issues with the Katz Eye screen even at maximum aperture. Meter sensor angle relative to the split, perhaps?


07-28-2013, 12:00 PM   #32
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Ok, ok, ok... I think I figured something out. A big thanks to stevebrot for the reference to the owner's manual! It got me thinking a bit.

I have a Ricoh 35-70mm K-mount zoom lens that I use in manual (M) mode. The green button is programmed for Tv Shift. I zoom, focus, set the aperture, press the green button for an exposure setting, and take the picture with the shutter button. All of this is done through the optical viewfinder. Everything works great because the exposure reading is done directly through the sensor itself.

My M42 lenses don't work like this. I am unable to press the green button to lift the mirror for the sensor to measure the light for an exposure. The exposure is instead determined by whatever passes through the optical viewfinder (or through the autofocus section if the exposure metering is there).

This morning I quickly tried using Liveview with my M42 Jupiter lens on a few random subjects and the exposure is right on!

Why can I not lift the mirror with my M42 lens in manual mode when using the optical viewfinder? Am I missing a setting? Is this an oversight on my K-30?
07-28-2013, 03:57 PM   #33
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QuoteOriginally posted by stevebrot Quote
That may well be a factor, though my K10D has spot metering issues with the Katz Eye screen even at maximum aperture. Meter sensor angle relative to the split, perhaps?

The blackout I am referring to is the blackout caused by the split image and/or microprism ring. They change the value of the light transmitted where the spot meter is pointed. This has always been a problem with through the lens spot metering.

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