Understanding club speed
Golf estimates clubhead speed from video by tracking the club's position across consecutive frames and calculating how far it traveled in the time between them — the same underlying idea as a radar-based launch monitor, without the dedicated hardware.
Accuracy depends heavily on frame rate and camera setup. A high enough frame rate to capture the fastest part of the swing without motion blur is essential, along with the recommended camera distance so the club stays a large, trackable object rather than a few pixels wide.
Under the recommended setup, video-based estimates typically land within a few miles per hour of a radar measurement — close enough to track real progress over weeks, even if it isn't quite launch-monitor precision on any single swing.