I actually get a tiny bit of lag on the shutter button fairly often. I can see that messing up the timing for something like this as well. I'd bet the R5 has this worked out... hopefully. It's never been a problem for what I shoot, but it is noticeable.Earlier this spring, before the coronavirus apocalypse, I was shooting portraits of softball players. They all wanted pictures where they threw the ball up into the air and stood looking at the camera with the ball in mid air. I was trying to shoot with the R and no matter what I did the viewfinder never matched up with the shutter/flash. There was always a lag and I had to just guess and pray. A few days later, I tried it with the 5D4. No problem. That's when it really became apparent to me. Example attached. I did it, but it took many more tries and as I say, I just had to guess and not rely on the viewfinder.
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