Canon 35L and 1DMKIIN Focus Point test shot
I've seen focus errors with the 35mmL. it has such a shallow depth of field ar close distances, that it often needs to be calibrated to the camera due to normal camera body / lens variations. I sent mine to CPS after it required a +17 on my 1D MK III. They noted that it was adjusted on their gold standard 1D MK III, and it was right on when I got it back.