Did you know that the photo-finish cameras at the Tour de France take 10,000 pictures a second? Well, you will in a minute.
ITV Sport's Matt Rendell talks you through the exact science of timing each and every rider in the Tour de France: in 2010, the narrowest gap was between Robbie McEwen and Edvald Boasson-Hagen in Reims, at just three ten-thousandths of a second.
What about time gaps? It's simple: if the back wheel of the rider in front is ahead by 0.999sec or less, there is no gap. Any more than that and a shake-up in the GC awaits!
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