I think with fast communication RF lenses will give us the best tracking experience and probably will give us more keepers. What Tony did was not ideal at all.
It's looking good so far. Tony's lens was definitely ideal, but still did OK. Looking forward to the reviews of the R5 with the new RF 100-500 L.
Best,
Like many others I have many EF lenses and a few third party as well.
I do know and accept the RF will work better in the EVF for RF lenses that EF lenses with the difference in performance being technical advance powered by the new capabilities in the RF lenses.
Canon has said many times that the EF lack the speed of communication capability between the lens and camera in this 30 year old EF lens link. New focus motors change things autofocus capabilities too.
I thank you for pointing out the blackouts in the Canon EOS R5 & R6 Animal AF BLOWS MY MIND! Wildlife review. I like Tony and Chelsea as well as Fro and others. I think most are well intentiond straight shooters sharing their feelings while performing some to maximize clicks. However, you have to be careful and interpret what they say with some thought about their charistic individual traits. Chelsea is quite different than Tony.
I am worried like many that the EVF in the R is not as good as the excellent, IMO, EOS 5D Mk IV. I know the tracking is better both from the reviews and my personal experience with the EOS R. The 5DIV has blackouts but the tracking performance is good because human shooter can work around this ignoring them while doing acceptible flying-bird- back-by-sky tracking as well many other kinds of wild tracking. Ugly perhaps. However the 5DIV is very function for doing this. I have less experience with A9 Sony EV but it is mirrorless and looks to have very functional EVF.
I do use the EOS R for wildlife and bird shooting. It is workable but less than ideal. I like it best for 2.5fps burst mode and Servo AF of all the setting options. Faster 5fps HS burst seems worse for tracking. I do prefer the EOS 5D with the faster burst shots but I am now use the EOS R in self training preparation for the new mirrorless generation like the R5.
I know Tony titles the new Youtube AF BLOWS MY MIND and I believe he is right about that when using his EF500mmf4 + 2X TC lens. He say it is a completely unfair test and his only object was tracking bird eyes as subjects. He includes the amazing ablity for the focus tracking on a fast flying kingfisher but mostly about small birds in bushes. The AFII picks out the focus with more speed than Tony. He says it is pretty accurate.
AFII looks to be great and Tony says better than year old models of Sony but has not tried the newer about be released model. I care more about EF100-400mm ii with 1.4X iii TC though.
Fro was impressed with the zoo shots and the tracking ability in the 1DXIII for basketball issues. Basketball matters to me as well as birds. Probably even more than birds. The issues are different. F1.2 focus issues are different too. Subsequent comparisons and ranking the importance of each is complicated.
From this review evidence is see it likely the EVF is not perfect. Blackouts are not pretty or ideal in any EVF. However, do not impede tracking per se as the 5DIV demonstrates. Freezing however is concern if the freeze duration occurs over many milliseconds. The eye is sensitive to the jerks. In reviewing the Fro video CANON EOS R5 Human Eye AF: WOW...WATCH OUT SONY!!! at 1:23 is see of freezing jerks in the running boy. This looks better than the EOS R freezing and we know nothing out the burst rate or fps he is using here. At 20FPS the sensor readout is 4X the time than greater than at 5FPS which is still a useful shooting speed that does not cause as more workflow. I am not thinking I need 20 fps for most applications. A good 10fps would still be incredible and be above my expectations for the purchase of an R5. Fro says the AFii shooting is pretty close the the Sony AF and he owns an A9II as well as an A7rIV as his primary cameras. He also says the focus beat the Nikon AF and that he was please with the AF that he could rely on and was easy to change AF subject selection better than the Sony.
I have my 9am July 9 pre-order in and have no intention to cancel. I am likely to return a camera and have never done so. I use what I get the to best of it's capability that I can work out.
I do think I may buying the RF 100-500mm if the viewfinder tracking is better but I was impressed enough in my initial RF lens buy of RF24-105, RF 35, & RF24-240mm leneses for my EOS R that I have gone back for the RF15-35 & RF24-70 which was a bigger commitment. Now the EOS R5 is the next step after my initial use with the EOS R. I will keep my 5D and EF L glass forever. Maybe it remain be better at extreme tracking but it will not match the AF of the mirrorless cameras. Particulary when using TCs or at low light. I hope the 45MP of the R will make my cropping a little better. Every bit helps.