I have a K10D and recently got a Pentax-M 28mm lens, k-mount lens. I chose the 28mm SR setting, and press the AE-L before the shutter button, but I cannot get a meter reading, whether the diaphragm is stopped down or not. The "allow f-stop ring" is activated. The diaphragm does close down when the shutter releases. If I set the right shutter - f-stop settings the exposure is right. But the camera gives me no clue as to what the setting should be. Do I have to get a manual meter? Explanations I have seen on the net say that you should get a reading. ???????