Every Olympics, a few races boil down to scream-at-the-TV finishes that are so close, viewers can’t tell who won. The timekeepers live for those moments. "If everything is clear, nobody is talking about timekeeping. We love to find close races," said Peter Hurzeler, a technical guru who will be working his 16th Olympics this summer for the Games' official timing company, Omega. While all venues will use sophisticated timing and scoring systems, those at the track and the pool are particularly elaborate. Here are two of the setups that will allow Hurzeler and roughly 1,200 technicians and volunteers to tell us, without a doubt, who wins.