A PHOTO FINISH

Last night Jamaican Shelly Ann Fraser-Pryce defended her title as the world's fastest woman edging out Carmelita Jeter of the US  by .o3 seconds to win the 100-meter final. I love this image of the photo finish which NBC flashed on the screen.  

The photo finish uses a special camera that exposes only a sliver of the image by light coming through a vertical slit.  Any still object along that slit appears as a streak and thus these beautiful abstractions emerge.

Photo-finish cameras are used at track meets, horse racing, swimming and anywhere else where the winner is determined by competitors crossing a finish line.  In track, any part of the torso which hits the tape first wins, which is why you often see these dramatic lunges at the finish.  The margin of victory is often hundreths of a second and only the camera knows the winner.

Below are some other famous photo finishes...

OLYMPIC TRIALS 2012

Prior to the Olympics at the US Trials, Allyson Felix and Jeneba Tarmoh hit the finish line at exactly the same time during the women's 100 meter race. Both came in third place, the last spot left to make it on the US Team. After some controversy and a proposed run off, Tarmoh conceded her spot to Felix.

BEJING 2008
In 2008 Michael Phleps outtouched Milorad Cavic by .01 seconds in the 100 meter Butterfly to win his seventh of eight record breaking medals. This image is by Heinz Kluetmeier of Sports Illustrated, who was the first person to put an underwater camera in the pool at the 1992 games.

1956 HOTHAM HANDICAP

Perhaps the most famous photo finish of all time was a triple dead heat with three horses hitting the finish line simultaneously at the Aqueduct Racetrack in New York.