EOS R6 - AF not on target on few pictures

Per other comments, I think the red focus square is cheated sometimes in bad lighting.

I think I can replicate this one with my R5 if the subject is moving. Based on some experiments, there seems to be a lag between face/eye detection and focus locking. Probably made worse by poor lighting. I did the experiment in reverse and moved the camera aimed at a mannequin head with similar shutter, f-number, and ISO settings (i.e. in dim light). The focus box was moved in the direction of the camera and the focus was messed up (not just with motion blur). The focus box was lagging behind the subject. I think if the camera was steady and the subject move, the camera's focus could be messed up.

Per my much earlier comment, You might want to experiment with having two back buttons and uses a point focus. A least it might be worth a try.

When I looked at the information you provided, it does seem like you were correct and have a real problem, which makes it impossible to solve by doing something differently. I'm reminded of a Mark Twain story (condensed version below):

Mark Twain once wrote about a lady whose health was failing and who had no bad habits like drinking or smoking to give up. There she was, quipped Twain, a foundering ship with no ballast to throw overboard to lighten the load.

Full Quote here: https://quoteinvestigator.com/2011/04/24/sinking-vessel/

Chris_From_Holland wrote:

R2D2 wrote:

Chris_From_Holland wrote:

R2D2 wrote:

Don’t need RAWs if you just post some screen shots from DPP (with AF points showing). Do include EXIF tho.

TIA, R2

One more photo:

Thanks for these. I've seen this phenomenon reported here before (here's one of the threads)...

https://www.dpreview.com/forums/thread/4551441

I think the AF algorithms try to paint a happy face on occasion (indicating AF lock when not actually in focus ). The cymbals just seem to be a much better AF target than the face (esp in lower light), even when the cymbals are not under the reported AF square.

There are still occasions esp in low light (IME) where Spot AF produces better accuracy. In fact, I suspect that you will get close to a 100% hit rate under these conditions (vs Face/Eye detect).

R2

ps. I've always suspected that the AF frame designation is actually done post-shot, and is not a real-time indicator of focus. Just a theory...

The thread is indeed this behavior.
I'm not surprised, I'm not shooting in the easiest condition either
I do switch between Spot AF & Tracking, but until now, I was seeing clear hesitation of the AF the the EVF. It's the first time I see this this specific case (and well, this photo was cool).

I love so much my R6, that I tend to forget that it may have limits Hence I'm still learning its limits