A. Virgo, Football Genius
- Jul 21, 2003
it is someone putting lines on their screen, going back and forth to select a frame. we saw exactly how it works in the mis-communication fiasco weeks ago. there is no hawkeye here because they cannot track 22 people and a ball, all moving at variable speed across hundreds of sq meters. hawkeye relies on camera aligned to static lines, only the ball has to be tracked.They have several VAR cameras and all the broadcast angles to choose from. So they can choose the one that shows the body part clearly and draw the line using that angle. When they then switch angles to assess other relevant information, the line stays in place. The cameras are calibrated to work together and even take into account the camber of the pitch.
It's precision Hawk-Eye technology, not someone putting a straight line across a single still frame as TV companies used to do. That explains why some stills that look onside/offside on traditional coverage were misleading. It's a different outcome once the viewing angle has been accounted for.
Personally, I hate it as it takes too long and there's nowhere near the leeway there should be in a high speed sport - but the process is pretty much sound.