I've been noticing that my 5d3's outer AF points are producing a ton of out of focus photos.
I'm referring to any outer focus point aside from the center cluster, however, I almost always have it set to cross type points only, so assume that I'm talking about the outer cross type focus points. Also assume that I use single point or spot AF selection (well, unless I'm tracking a moving subject, then I use expanded or zone AF). And unless something is moving, yes, I'm in one shot. Sorry, but I'd like to avoid the annoying 'user error' comments.
It's been particularly frustrating because I have purchased FIVE sigma 50mm 1.4 art lenses and returned them for having focusing problems, which may actually be due to the 5d mark iii, at least in part, though they acted funny on my 6d as well.
What's happening is with fast primes, the center focus points work fine, but using any outer focus point (cross type) results in front focusing. I tried my friend's 5d3 and hers was doing exactly the same thing but slightly worse. This is particularly frustrating because using AFMA to correct for the front focusing of the outer points throws off the center points.
Anybody else experience this? I had this EXACT same problem when I had a 7d a few years ago and even after two trips to canon service it was still doing it, though to a lesser degree.