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    (Wikipedia) - Darkness   (Redirected from Dark) "Dark" and "Absence of light" redirect here. For other uses, see Dark (disambiguation) and Absence of light (disambiguation). This article is about the opposite of light. For other uses, see Darkness (disambiguation).The Creation of Light, by Gustave Doré

    Darkness, the polar opposite to brightness, is understood to be an absence of visible light. It is also the appearance of black in a colored space.

    Humans are unable to distinguish color when either light or darkness predominate. In conditions of insufficient light, perception is achromatic and ultimately, black.

    The emotional response to darkness has generated metaphorical usages of the term in many cultures.

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    Scientific PerceptionStare at the image for a minute, then look away. The eye supplies the light and dark complements to the image.

    The perception of darkness differs from the mere absence of light due to the effects of after images on perception. In perceiving, the eye is active, and that part of the retina that is unstimulated produces a complementary afterimage.

    Physics

    In terms of physics, an object is said to be dark when it absorbs photons, causing it to appear dim compared to other objects. For example, a matte black paint does not reflect much visible light and appears dark, whereas white paint reflects much light and appears bright. For more information see color.

    Light cannot be absorbed without limit. According to the principle of the conservation of Energy, energy cannot be created or destroyed; it can only be converted from one type to another. Consequently, most objects that absorb visible light reemit it as heat. So, although an object may appear dark, it is likely bright at a frequency that humans cannot perceive. For more information see thermodynamics.

    A dark area has limited light sources, making things hard to see. Exposure to alternating light and darkness (night and day) has caused several evolutionary adaptations to darkness. When a vertebrate, like a human, enters a dark area, its pupils dilate, allowing more light to enter the eye and improving night vision. Also, the light detecting cells in the human eye (rods and cones) will regenerate more unbleached rhodopsin when adapting to darkness.

    One scientific measure of darkness is the Bortle Dark-Sky Scale, which indicates the night sky''s and stars'' brightness at a particular location, and the observability of celestial objects at that location. (See also: Sky brightness)

    Technical

    The color of a point, on a standard 24-bit computer display, is defined by three RGB (red, green, blue) values, each ranging from 0-255. When the red, green, and blue components of a pixel are fully illuminated (255,255,255), the pixel appears white; when all three components are unilluminated (0,0,0), the pixel appears black.

    Cultural ArtisticCaravaggio''s The Calling of St Matthew uses darkness for its chiaroscuro effects.
    This section does not cite any references or sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (January 2010)

    Artists use darkness to emphasize and contrast with light. Darkness can be used as a counterpoint to areas of lightness to create leading lines and voids. Such shapes draw the eye around areas of the painting. Shadows add depth and perspective to a painting. See chiaroscuro for a discussion of the uses of such contrasts in visual media.

    Color paints are mixed together to create darkness, because each color absorbs certain frequencies of light. Theoretically, mixing together the three primary colors, or the three secondary colors, will absorb all visible light and create black. In practice it is difficult to prevent the mixture from taking on a brown tint.

    LiteratureSeparation of light and darkness on the first day of creation, from the Sistine Chapel ceiling by MichelangeloFurther information: Light and darkness

    As a poetic term in the Western world, darkness is used to connote the presence of shadows, evil, and foreboding.

    The first creation narrative begins with darkness, into which is introduced the creation of light, and the separation of this light from the darkness (as distinct from the creation of the sun and moon on the fourth day of creation). Thus, although both light and darkness are included in the comprehensive works of the almighty God — darkness was considered "the second to last plague" (Exodus 10:21), and the location of "weeping and gnashing of teeth.” (Matthew 8:12)

    The Qur’an has been interpreted to say that those who transgress the bounds of what is right are doomed to “burning despair and ice-cold darkness.” (Nab 78.25)

    In Chinese philosophy Yin is the complementary feminine part of the Taijitu and is represented by a dark lobe.

    The use of darkness as a rhetorical device has a long standing tradition. Shakespeare, working in the 16th and 17th centuries, made a character called the "prince of darkness" (King Lear: III, iv) and gave darkness jaws with which to devour love. (A Midsummer Night’s Dream: I, i) Chaucer, a 14th-century Middle English writer, wrote that knights must cast away the “workes of darkness.” Dante described hell as “solid darkness stain’d.”

    In Old English there were three words that could mean darkness: heolstor, genip, and sceadu. Heolstor also meant “hiding-place” and became holster. Genip meant “mist” and fell out of use like many strong verbs. It is however still used in the Dutch saying "in het geniep" which means secretly. Sceadu meant “shadow” and remained in use. The word dark eventually evolved from the word deorc.

    Tags:Chinese, Dutch, Physics, Wikipedia


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