The Canon EOS 70D delivered very impressive AI Servo performance in my 800+ image session with the cantering and galloping quarter horse. Even in the light rain.
The four hooves in the air illustrate the speed this horse is moving at. And the human subjects rarely give any argument when asked to ride for me.
For this photo, I was using AI Servo mode (of course) with the center AF point selected. I did my best to keep that AF point pinned on the horse's right shoulder and the rider's right stirrup to cause the plane of sharp focus to land near the rider's face.
Camera and Lens Settings
300mm f/2.8 1/1600s
3648 x 5472px