« on: December 20, 2013, 09:16:33 AM »
Used the 85II on a portrait session yesterday and was getting a pretty high percentage of slight misses on a relatively static subject. I did pretty well with the same lens on my 5D3. Since switching over, the 85II has been pulled out twice for any significant amount of shooting and both times have been tough with regard to getting a lot of misses.
I'm going to go out on a limb and assume you have done a proper AFMA with the lens. I haven't used the 85II myself with a 6D or otherwise, but I don't have any issues with the 135L; I get consistent, repeatable results. The 85II should be usable on a 6D; plenty of people were shooting with it on a 5DII, which I can attest had a slightly inferior AF system to the 6D.
AFMA'd with Reikan FoCal three consecutive times yielding the same result. Figured it was good enough. I surprisingly have had the same findings as you regarding the 135 on the 6D. Seems to be just fine. But for some reason, the 85II on both occasions has been somewhat unreliable compared to when it was paired with my 5d3. The other ones that have given me the most problems is the 24II and the 24-70II. The zoom wasn't unreliable as far as AF goes, just seemed to hunt noticeably more in and in decent light which was odd. Most the other stuff has been fine.
That is interesting. I wonder if it due to the nature of the newer lenses being optimized for 1DX and 5III AF? I'm actually very surprised at more hunting with the center point, which has (on paper) greater sensitivity to anything else Canon has. I always use single point AF, myself, and in good light I don't have problems with any of my lenses on my 6Ds. And that center point can lock onto just about anything in any light.