Cody Taylor

Light graffiti, also known as light painting is a photographic technique in which exposures are made usually at night or in a darkened room by moving a hand-held light source or by moving the camera.

CurtMonash writes “Fandome offers a fascinating video explaining how the first-down line on football broadcasts actually works. Evidently, theres a lot of processing both to calculate the exact location being photographed on the field — including optical sensors and two steps of encoding — and to draw a line in exactly the right place onscreen. For those who don’t want to watch the whole video, highlights are here.”

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