I think I have finally got these cameras figured out. At least for basic use. The a9 and the a7r4 are very similar in design, with the main difference being the sensor.
For fun I decided to crank up the shutter speed for a few hundred images the other day, to 1/32,000 - interesting! Even for these speedsters, i think 1/10,000 of a second would work fine. But it is cool to see pin-sharp feather detail on a duck flying by at such a speed.
So at 20 frames per second, short bursts of 3-5 images seemed to do the trick, and give me enough selection to pick out a few to edit.
The neat thing here? 852 frames on this sunny morning, and maybe 4% of my shots where I missed focus. More then amazing, these cameras focus like nothing I have seen! The main reason I missed? The AF button on the back of the camera is too small for my fat thumb! I need to figure out a dependable way to extend that button!
The new a9II and the a7r4 both have much nicer back focus buttons, and I did have a better percentage of sharp shots with my a7r4 last week.
thanks for looking!
Female Long-tailed Duck in Flight
Sony Alpha A9,Sony FE 100-400mm F4.5–5.6 GM OSS
1/32000s f/5.6 at 400.0mm iso5000