I have an ongoing thread on the Canon EOS 5 as a next purchase, used with a adaptor and EF lenses.
I assume the same pretty well all criteria in terms compatibility with
EF lenses are the same for the R5 and the R.
Any opinions on the comparison between the EOS R and the 5D4, in terms of image quality and AF performance.
I have no great interest in video, beyond the most basic.
Would the R be a worthy replacement for a 5D3 over a 5D4?
I really do baulk at paying the R5 price., I'd rather give the difference in price to my son and his partner to have their bathroom redone.
£2000 better spent?.
MDE
The R is a perfectly fine camera. However, it is no 5D III or 5D IV for that matter. If all you care about is image quality and AF, the R is definitely in the same league as those other cameras. However, the R's shutter is so amazingly loud in full mechanical mode... if you are in a quiet space the R's mechanical shutter is frankly absurd. Any 5 series camera is much, much quieter. Now I am used to the R5, it is by relative volume almost silent. 99% of the time I used the R I used it with EFCS due to that loud shutter. It's the one thing about the R that is a little unseemly and perhaps not representative of the price tag. It manages to be louder than the 6D II, and the 6D II is flipping a mirror and a shutter!
Other things about the R I hated, well, people talk about the R5 having bugs... The R was worse. I had it quit working in the middle of a shoot at least half a dozen times. Sometimes a power cycle fixed it, sometimes I had to remove and reattach the lens, sometimes I had to remove the battery. Then later it started to have problems with the battery grip. Maybe it was my fault using an RF 28-70 and hanging it on a holster by the tripod mount but regardless of the causes the fact is it started to have issues staying connected to the battery grip.
On top of it all, the R also had some odd exposure issues. It probably had something to do with the EFCS but regardless it would randomly start exposing the edge of the frame a little brighter. A power cycle would fix it, if I caught it while shooting. Unfortunately I missed it a number of times that it started happening.
The R also seems much more sensitive to the lens choice. With RF glass it was great but with some other lenses it was a little janky. It needs to have a really tight image on the sensor compared to the R5 which seems to do better with less contrasty lenses.
If I was trying to decide between R and R5 no question I would get the R5 100 times out of 100.