Originally posted by blende8 Feel free to repeat the test with a grey card.
Anyway, with the K10/K20 you get overexposure of about +2 EV at higher apertures, with the K7 this is much less, but still not perfect.
It would be nice if one could do a calibration curve with a certain lens on the body. The calibration is then stored in the camera.
I agree, I think the camera (k7) still has a problem at fast apertures but I agree fully that at middle to small apertures the K7 meters much better, a fact displayed by the metering with my 2x TC on my 70-200F2.8 being spot on as opposed to +1.5 stops over exposed.
The problem with a calibration curve is that the camera does not know maximum aperture or minimum aperture,
BUT if you could enter maximum aperture I am sure the metering behaves in a consistent manner so they could calculate the preset aperture by the change in exposure, it just would not be as linear as you would expect.
You should propose this to pentax, they haver stopped listening to me on the subject of metering with K mount lenses