Originally posted by Yosemite Thanks for the informative post. I have the same backfocus issue with my K10D and 21mm Limited. Pentax service replied by email that I should send the camera and lens for service; they also said that the camera would focus correctly with other lenses.
When I made the correction using Debug, fixing the backfocus on the 21mm Limited made the other lenses frontfocus. How do your other lenses perform? Did you notice any change?
I don't really know because my other lens, the 70mm DA Limited, is on my other K10D body. These two lenses do it for me and the two bodies eliminate the need to change lenses. But before I sent in the one body and the 21mm DA Limited, I tested my 70mm on that body and it autofocused perfectly.
As for the Debug mode on the K10D, I've never used it. I prefer that Pentax fix defects. Being without the camera for a short while was no problem for me because I have other digital cameras besides the second K10D body. I also now have a one year repair warranty for the body that I sent in. Anyway, I could not have have replaced the baseplate with the infamous chip myself.
Richard