Originally posted by stevebrot OK...equivalent to shooting with Pentax-K or Pentax-M lens having no contacts on the base. BTW, this is not related to dimming the display, but you may want to check whether the lens is stopping down for exposure. Some TCs have non-conductive bases. Those are not detected as K-mount by the camera and the aperture actuator will not operate for exposure or green button metering.
Steve
Oh, now I understand your comment earlier about the conductive base. The TC does have an aluminum mount and a movable post on the camera side which couples to a movable post on the lens side (f-stop indicator or aperture actuator??). Opposite that it has a curved slot that goes clear through from camera side to lens side.
I think the lens was stopping down because I adjusted the exposure to several different f-stops on the lens ring and I believe that was reflected in the exposure but now that you mention it, I would have to check to make sure.
The camera gave a readout of the shutter speed, but the f-stop readout was F--, and didn't indicate the f-stop (which makes sense since the camera has no way of knowing what TC is being used so it has no idea of the true f-stop). I just assumed I was setting that on the lens and the actual f-stop was 2x that value. Will check to see if the lens is stopping down tomorrow also.
Thanks Steve for your input. I had some clues in the old film days but it's a learning curve for the K-1.