Re: Win a home paint makeover with Homebase Worth over £3,000

On Thu, 27 Aug 2009 14:19:42 +0100, Mike wrote:

Actually you're both right as there are many different sets of primary
colours.
RGB (red, green and blue) are additive primaries, as used in
televisions. Yellow being a combination of red and green.
RYB (red, yellow, and blue) is a historical set of subtractive primary
colours. Mainly used by painters.
YMC (yellow, magenta and cyan) is a modern set of subtractive
primaries used by printers, usually with black. To print red, yellow
is overprinted with magenta.

My understanding is that what printers used to refer to as red, yellow and
blue were actually magenta, yellow and cyan - although the M & C were not
necessarily pure.

http://en.wikipedia.org/wiki/Primary_color#Additive_primaries is
informative, particularly in respect of the RYB model:

"During the 18th century, as theorists became aware of Isaac Newton’s
scientific experiments with light and prisms, red, yellow, and blue became
the canonical primary colors—supposedly the fundamental sensory qualities
that are blended in the perception of all physical colors and equally in
the physical mixture of pigments or dyes. This theory became dogma, despite
abundant evidence that red, yellow, and blue primaries cannot mix all other
colors, and has survived in color theory to the present day."

This is quite handy too: http://www.rgbworld.com/color.html

--
Peter
.

Relevant Pages

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