Originally posted by orcrown I am sure that I don't press on the green button. I am using 35mm f2,8 ltd. macro, Sigma 10-20,50-200mm. Yesterday I tried and tried many times and the result is the same. I set the values as I want and when I press on the shutter release, camera turns its values and pictures get dark or overexposed. Please help I don't know what to do.Thanks.
Try putting the camera in P mode or even Green mode just to see if the meter is working correctly.
Then post a picture or two (with the EXIF included), shot in M mode and note what you wanted the shutter, aperture and ISO to be and what changed.
I routinely use the P mode on my K10D, but I tried the M mode, just to see if I could accidentally make the camera do as you say. It never happened.