bit late to the party but that gave me chance to read people comments about AF fixes before i did upgrade so i did some before and after of same objects and i see huge change in AF performance.
before i had to set -6 to get 50/50 spot between inddors and outdoors, now i reseted AF fine tunning to 0 and my worst lens (sigma 17-50 f2.8 hsm) works really well now no metter the conditions, just as good as when used with live view focusing.
i'm yet to test it real night conditions under indoor lighting but my basement test with minimal sunlight going in under the house seem spot on as well so i expect no change there fingers crossed.
even my old FA50 wide open at f1.4 is sharp and crisp like never before with AF
only sad thing is that we had to wait for this fix for so long, i virtually stopped using my K5 that i got in 2010 because of this AF mess, i could find my way around it but i do photography for fun and it was just getting too much "ok lets dial in different AF setting yet again or shots will be ruined"
EDIT: now that got dark in my office room i did tungsten light AF test and still with fine tune AF on 0 (off) my FA50 focuses spot on even wide open !!!! I hope this is not a dream
Last edited by Croc; 05-23-2012 at 12:26 AM.