Originally posted by J2R Well, I used an M series lens,........
Aha, that adds another element to the equation !
Quite a few of us on here use the old "K" and M series lenses, including Marc and myself.
Now it is a well known fact that the K10 (and K20) will lead to progressively overexposed shots as you stop down. The degree of overexposure is variable depending on the lens in question. I wont go into details as to why, there are hundreds of threads on the subject, and it is caused by the standard focus screen.
The upshot is that you will have to use the histogram more and make adjustments yourself to aperture and/or shutter screen to get the exposure right. Just pressing the green button wont always give you "correct" exposure.