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08-01-2010, 10:33 AM   #1
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Front back focus calibration on K20D

Hello guys, recently I bought a DA* 16-50 and yesterday I found out that some pictures shot at 50mm f/2.8 were out of focus.

Today I made some test with a couple of objects and it results that my K20D + 16-50 is affected by front focus.

I tried to calibrate it, and here is the result:
(focus on the middle battery, crop 100%)



My best result is when the calibration is set to +10. I would like to increase this value in order to improve the autofocus tuning. Is it possible in some way?


08-01-2010, 12:08 PM   #2
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Yes, there is an easy way to use much higher calibration numbers by setting the camera in DEBUG mode. Let me stress that this should be the last thing you try after the suggestions above, including returning the new lens if it is way out of wack compared to all your others.

Andy McMullan: Debug mode on the Pentax K20D DSLR

I have used this in the past with no problems but I love to tinker even if I shouldn't.
08-01-2010, 09:06 PM   #3
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Can you post the resized / uncropped version? Are you sure the closer battery was not within range of the selected focus sensor?

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