I had to replace the batteries in my Pentax spot meter (analog), and the unit now seems to be out of calibration. I know there is the test button and adjustment screw to calibrate. I think I once read that when holding down the test button one should adjust the screw so that the needle is pointing to a certain EV value and then it's good to go.

Is that correct and if so, is that EV value '12'? Is there anything else I can do to verify accuracy?

Many thanks,