Wow. Take a look at this...

[APG]

Originally Posted by SamG

And another thought... broadcasts (from college to pro) are used all the time to review last second shots. They use the same technology that was shown in the reply (game/shot clock superimposed over game camera). If the system is inaccurate, why use it?

I know, at least in the NBA, they aren't using superimposed clocks. Since the game clock is the first clock of importance when determining the end of the period in the NBA, they're using shots with the game clock in the view of the camera (followed by LED lights which is next on the list when determining end of period/shot clock period).