I just did a test using my Pentax-FA 50mm f1.4 lens. I put a piece of scotch tape over the pin that is just to the left of the screw on the camera body at the 6 oclock position. My lens now appears to work as a MF -M or -K lens. I set the aperature on the lens, set the AF/MF switch on the side of the camera to MF, focus the lens for focus trap, set the AF/MF back to AF, press the AE-L button, press the shutter all the way, now move something into the focus trap area (my hand in this case) and the camera fires.

Would someone care to verify that this works with their AF lens also.

See the site at http://www.robertstech.com/matrix.htm and the pin I am talking about is the one that reads "Data".

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Ron ~ Retired, just taking it easy with life, and not getting bothered much by these brain excercises.
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