Is it possible to keep the EVF on the R3 on at all times? Even when we switch it to EVF only mode it blacks out when your face is not near the eyepiece. That wouldn't be a problem if the blackout lag wasn't so bad. Both me and my colleagues haven't figured out a way to keep it on constantly. We shoot sports and it has cost us a few shots since you often need to switch between your laptop and camera quickly.
While you can keep the EV on continuously, as indicated by my colleagues, doing so chews through your battery capacity, so you might want to consider that. The sensor that activates the EVF when you move your eye to it is the most energy economical way of doing this, as you won't really need the EVF if you are not looking through it.
I tested an R3 on loan shortly after they came out and at least at that time there wasn't a way around this issue. Maybe the firmware has been updated in the ensuing months.
I shoot sports using multiple bodies (typical 70-200 f2.8 on one and 400 f2.8 on the second) and this issue was one of the reasons I would never consider the R3 to replace my 1DX III bodies. In football it isn't unusual to switch between bodies during the same play and any startup and/or viewing lag makes that technique unworkable.
It is fine for a lot of uses but its functionality isn't there for sports yet as compared to Canon's top DSLR designs. Maybe Canon will come out with a R1 series that doesn't have the lag and freeze issues like the lower level R series.
09/26/2023: New firmware updates are available.
08/18/2023: Canon EOS R5 C training series is released.
07/31/2023: New firmware updates are available.
05/31/2023: New firmware updates are available.
05/18/2023: New firmware updates are available.
03/30/2023: New firmware updates are available.