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Dave Plowman (News) Dave Plowman (News) is offline
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Default TV Studio shows - red lights on set ?

In article ,
Mark Carver wrote:
On 13/06/2019 16:31, NY wrote:


As a matter of interest, why is it that they used to use blue
backgrounds and keying for Chromakey but nowadays almost always use
green? I thought that blue was chosen because it was the least likely
primary to be contained in the foreground subject, and the most
diammetrically opposite to flesh tones which are the absolute worst
thing that they want to cause false triggering.


The use of blue was a throw back to 'film chromakey', which I think was
the easiest colour to separate out in that process.


I was told in BBC training that blue was chosen from RGB because there was
less of it in flesh tones. So gave the best separation to faces.

Green is chosen for contemporary video chromakey, because it constitutes
a higher proportion of the signal, requires less illumination, and
therefore generates a better 'mask'.


I thought green was the original colour used in proper film?

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