One of the most spectacular elements of the opening ceremony of the Beijing Olympics was actually a special effect created for television viewers around the world. Giant marching aerial footprints outlined by fireworks were created by sophisticated computer graphics digitally inserted into the live coverage, reports the Daily Telegraph.
All 29 steps were actually formed with fireworks, but the 55-second sequence effect was created because it would have been too difficult to use cameras to capture them all. "We could not put the helicopter pilot at risk by making him try to follow the fireworks route," said an advisor to the Olympic Committee.
(Read more 2008 Beijing Olympics stories.)