Sprints

Film from the side with a steady camera. Keep the whole runner and both shoes visible, with space around them. Use bright, even light and keep bystanders out of the frame. Record at 120 or 240 frames per second when possible. Choose the unmodified original; rendered or slow-motion exports may change the timeline. In Photos on Mac, use File → Export → Export Unmodified Original. The app checks the imported file’s timing.