Speaking of Swallows, I was trying to shoot some Tree Swallows yesterday. Over the previous few days I was shooting birds like herons, ducks and geese that fly fairly straight. Locking on and tracking was incredible with essentially no viewfinder lag. Swallows were difficult to lock onto and much more difficult to track. I have to say, viewfinder lag did rear it's head a bit while trying to follow these swooping, darting, speed demons! I suspect I may be able to change the autofocus case or some parameters to improve tracking of birds that move like Swallows. Unfortunately it was starting to get dark and I didn't want to spend the time to change the AF case.Great write up and photos. Swallows are my holy grail of shooting BIF. I received my R5 but not the adapter so I have not been able to test shooting with my 100-400.
But I do have a question. I assume you had tracking turned on. Is there a way to select a subject and then begin tracking or is all up to the software? I notice I can turn tracking on and off with the joystick but I can't seem to make it start following a subject I pick. This may be user error or me reading the manual wrong but it seems to indicate you can pick a subject and then start tracking. What are your thoughts. FYI I only have a wide angle RF lens so it been limiting my wildlife test.
While I think with eye tracking af, I think there are ways to move the focus between detected subjects, but I'm not sure that works at typical BIF distances. If you find a way to make it work, please let us know.