The Romans had a greater
appreciation for the color green; it was the color of Venus, the
goddess of gardens, vegetables and vineyards.
The Romans made a fine green
earth pigment, which was widely used in the wall paintings of Pompeii, Herculaneum, Lyon, Vaison-la-Romaine, and
other Roman cities. They also used the pigment verdigris, made by
soaking copper plates in fermenting wine. By
the Second Century A.D., the Romans were using green in paintings, mosaics and
glass, and there were ten different words in Latin for varieties of green.
The perception of greenness (in opposition to redness
forming one of the opponent mechanisms in human color vision) is evoked by light which
triggers the medium-wavelength M cone
cells in the eye more than the
long-wavelength L cones.
Light which triggers this
greenness response more than the yellowness or blueness of the other color
opponent mechanism is called green. A green light source typically has a
spectral power distribution dominated by energy with a wavelength of roughly 487–570 mm.
In additive color devices such as computer displays and
televisions, one of the primary light sources is typically a
narrow-spectrum yellowish-green of dominant wavelength ~550 nm; this
"green".
Primary is combined with an longish red "red"
primary and a purplish-blue "blue" primary to produce any color in
between – the RGB color model. A unique green (green appearing neither yellowish nor
bluish) is produced on such a device by mixing light from the green primary
with some light from the blue primary.
By
contrast in process color printing, a subjective color system, green can be produced via a
mixture of cyan and yellow ink, and in traditional
color theory, green is produced by mixing yellow and blue paint.
Green is complementary to a purplish red or reddish purple
color, in both additive and subjective mixtures, and in simultaneous contrast effects and afterimages.
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