Why is a green screen green? © iStock

Why is a green screen green?

Green screens use a technique called chroma keying to allow the background image to be digitally changed - but why choose green?

Asked by: Andrew Eversett

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It’s a technique called chroma keying, where someone is filmed standing in front of a green screen. Any green colours are digitally filtered out and replaced by the desired video. If the subject wears anything green, the background image fills that in too, giving the impression the person has holes in them. Green is used as it is the least like skin tone.


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