This was last night with 2 dim 12volt RV lights as our only light (except the TV 10 feet to her left rear). One light was 5ft high and 5ft to her left front. The other was actually around the corner of the overhead cabinet. In other words, very little light. The camera was hand held up against the cabinet for stability. (I shake considerably) Focus had no trouble locking.
There is no PP, except sizing for posting.
This one I did a simple desaturate in PS.
E-p2, Sigma 30mm f2.8, Program mode.