Topic: AF micro-adjustment tool / technique

[Brian Skalinder]

Just stumbled across this tool and thread from a link at Pentaxforums.com (the TS of the Pentax world), after becoming increasingly frustrated with paper-based focus charts/tools/techniques.  Using those tools, I never could settle on whether I needed to micro-adjust my AF, because I achieved mostly mixed results -- both testing and in real life (mainly due to technique, not so much the camera/lenses).  Not so with this AF micro-adjustment tool.  Easy, fast, accurate, and quite precise (though obviously not perfect, since the goal is to maximize visible moire...a subjective feat).  Still, worked very well for me, and the micro-adjustments cured my slight back focus issue.

Original image:  http://www.openphotographyforums.com/forums/showthread.php?t=4708
Alternative image:  http://www.openphotographyforums.com/forums/showpost.php?p=41375&postcount=16 (original worked better for me)
Summary suggestions:  http://www.openphotographyforums.com/forums/showpost.php?p=56292&postcount=68

Most of the thread participants talk of micro-focus adjustments for every lens they own.  My Pentax K10D only supports a single, global micro-adjustment (unlike newer Pentax bodies, which support lens-specific micro-adjustments).  Still, I tested all my lenses, and to the best of my eyes' abilities, all my lenses now focus spot-on.  Seems improbable, given the different micro-adjustments most posters note for each lens, but...I've tested each lens twice and they all seem "on".

Anyway...hopefully others will find it useful.  But more likely, most of you long ago performed similar tweaking and I'm slow to get to it.

[phanophish]

I've really been eyeing one of these...

http://www.bhphotovideo.com/c/product/628452-REG/LensAlign_LA_LAP_LensAlign_Pro_Focus_Calibration.html

It seems like the one tool that really accounts for all of the variables (particularly plane of focus and lens alignment) and can give you reproduceable results, bit it is pricey.