Red Guide, Meaning , Facts, Information and Description
Red is a color at the lowest frequencies of light discernible by the human eye. Red light has a wavelength of roughly 700 nm. Oxygenated blood is red due to the presence of hemoglobin. Red light is the first to be absorbed by sea water, so that many fish and marine invertebrates that appear bright red, are black in their native habitat.Red is an additive primary colour, complementary to cyan. It was once considered to be a subtractive primary colour, and is still sometimes described as such in non-scientific literature; however, the colours cyan, magenta and yellow are now known to be closer to the true primary colours detected by the eye, and are used in modern colour printing. But in the RGB color model used on TV sets and computer monitors, red is one of the three channels, designated R.
Lower frequencies are called infrared, or far red.
A red filter used in black and white photography increases contrast in most scenes. For example, combined with a polarizer, it can turn the sky black. Films simulating the effects of infrared film (such as Ilford's SFX 200) do so by being much more sensitive to red than to other colors.
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2 Color coordinates 3 Variations 4 See also |
Usage, symbolism, colloquial expressions
Color coordinates
Hex triplet = #FF0000
RGB (r, g, b) = (255, 0, 0)
CMYK (c, m, y, k) = (0, 255, 255, 0)
HSV (h, s, v) = (0, 100, 100)
Variations
