Originally posted by sentro It does underexpose. I have a 100D super, a K10D and K20D. My K20D does underexpose by 1/2 stop.
Compared to the other cameras, you mean? And do you mean that the meter *chooses* a lower exposure, or that if you use M mode to set the same exposure on all three cameras, the K20D comes out darker at the same exposure settings? That's the source of confusion here.
If you are talking about the camera meter choosing a darker exposure, then that may well be (I have no way of testing that idea), but would not seem to be relevant here, since the OP is talking about manually making the same exposure settings on both cameras.
If on the other hand you are confirming his observation that for the same exposure settings, the K20D comes out half a stop darker, then great - good information to know. My guess is that might be deliberate, having to do with differences in the dynamic range of the sensor or the response curves applied in the in-camera processing.
But anyhow, I agree with your bottom line - none of this should be a big deal. Exposure is not an exact science, small variations are absolutely normal, and easy enough to adjust for.