Black

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Black
About these coordinates
About these coordinates
— Color coordinates —
Hex triplet #000000
RGBB (r, g, b) (0, 0, 0)
HSV (h, s, v) (-°, -%, 0%)
Source [Unsourced]
B: Normalized to [0–255] (byte)
Black cat, thought by some to cause bad luck (see superstition)

Black is the shade of objects that do not reflect light in any part of the visible spectrum.

Scientifically, black is not a hue (color); a black object absorbs all the colors of the visible spectrum and reflects none of them. This is sometimes confused with black being called 'a mixture of all colors', but that is not the case. In fact, an object emitting or reflecting all colors is perceived as white. Sometimes black is described as an "achromatic color"; in practice, black can be considered a color, e.g., the black cat or black paint.

Contents

  • 1 Color or light in science
    • 1.1 Absorption of light
  • 2 Usage, symbolism, colloquial expressions
    • 2.1 Neutral symbolism
    • 2.2 Positive symbolism
    • 2.3 Negative symbolism
  • 3 Black pigments
  • 4 References
  • 5 See also
  • 6 External links

[edit] Color or light in science

Black can be defined as the visual impression experienced in directions from which no visible light reaches the eye. (This makes a contrast with whiteness, the impression of any combination of colors of light that equally stimulates all three types of color-sensitive visual receptors.)

Pigments that absorb light rather than reflect it back to the eye "look black". A black pigment can, however, result from a combination of several pigments that collectively absorb all colors. If appropriate proportions of three primary pigments are mixed, the result reflects so little light as to be called "black".

This provides two superficially opposite but actually complementary descriptions of black. Black is the lack of all colors of light, or an exhaustive combination of multiple colors of pigment. See also Primary colors

† various CMYK combinations
c m y k
0% 0% 0% 100% (canonical)
100% 100% 100% 0% (ideal inks, theoretical only)
100% 100% 100% 100% (registration black)

In physics, a black body is a perfect absorber of light, but by a rule derived by Einstein it is also, when heated, the best emitter. Thus, the best radiative cooling, out of sunlight, is by using black paint, though it is important that it be black (a nearly perfect absorber) in the infrared as well.

In elementary science, far Ultraviolet light is called "black light" because, unseen (per se), it causes many minerals and other substances to fluoresce.

[edit] Absorption of light

In keeping with the law of conservation of energy, as a black color surface absorbs the light particles that hit it, the surface's particles are getting excited (excited particles = higher temperature).

[edit] Usage, symbolism, colloquial expressions

[edit] Neutral symbolism

[edit] Positive symbolism

[edit] Negative symbolism

Colloquially, black is sometimes used with a negative connotation. The reasons for this are various, but the most widely accepted explanations are that night is experienced by humans as negative and dangerous. A secondary reason is that stains are most visible as dark additions to pale materials. In traditional class-based Western cultures "pale" skin indicated genteel domestic or intellectual indoor-work as opposed to rough outdoor labor in the fields. Aspects of this black/white opposition are not unique to the West, as, for example in the Indian varna system and in Japanese Geisha makeup. African, Afro-Caribbean and African-American writers such as Frantz Fanon, Langston Hughes, Maya Angelou, and Ralph Ellison in particular identify a number of negative symbolisms surrounding the word "black", arguing that the good vs. bad dualism associated with white and black provide prejudiced connotations to "Color" terminology for race.

[edit] Black pigments