Igor, the K10D can be set to either +/- .5 or .33 stop variations. So, depending on how you set it up in the menu it would be controlled in that manner. If, however, you move the aperture ring off the "A" position and use the lens f/stop (and camera set to use that function according to the custom menu), then the exposure accuracy will still be good, you just won't know if you are at f/5.7 or 6.3, or whatever.
Walt -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net