Posted in the R3 thread also. I used the crop modes on each camera and processed in Gigapixel both to 7040 on the long side. The R5 wins under close inspection but the R3 held up very well being only 10MP vs 17MP. This was nothing scientific obviously but fun to see anyway. I used the R5 and 600mm at f4 and the R3 and 400mm +1.4x at f5.6. I cropped the R3 a little bit also seeing is was only 560mm vs 600mm. If you view the large image on Flickr you can see the best detail. Both handheld.
Wigeon courtship flight..files really get downsized here, pic is very sharp on my monitor at higher rez. What is optimal file size for this site I wonder...
I got a diving photo of this guy trying to catch something, unfortunately that is also when I learned that 1/2000 is too slow for a diving falcon as it came out with heavy motion blur.
Today was the first time I picked up the R5 after updating firmware. I think the AF is definitely "stickier" when it comes to fast moving subjects coming right at the camera. It didn't skip a beat tracking Pixel in the snow.