Late in the afternoon, shooting with the R5 and RF 100-500mm, as I was framing a distant kingfisher to see what kind of details I could get at that distance, I noticed that the critter was slightly out of focus when I put the EVF’s single point on it. But if I moved the single point (actually, a small square) just to the right of the critter, it snapped into focus.
After shooting with kid gloves on all day with the lens, trying to get critically-focused images and often failing, suddenly it all made sense. No, that didn’t enable me to figure out what the problem is, only to determine for certain that it’s the lens and not me! Prior to that, I was questioning my shooting technique, the stability of my normally very steady hands, anything I could think of that could be the problem.
So tomorrow it’ll go to Canon (finally!) and they can figure out what the problem is. LensRentals blogged about several instances of a cracked internal element in some of the copies they own. Dunno about a crack in mine, but something is definitely way off.
I’m just glad it’s not me.