Darkness, the direct opposite of
lightness
Lightness is a visual perception of the luminance (L) of an object. It is often judged relative to a similarly lit object. In colorimetry and color appearance models, lightness is a prediction of how an illuminated color will appear to a stan ...
, is defined as a lack of
illumination, an absence of
visible
Visibility, in meteorology, is a measure of the distance at which an object or light can be seen.
Visibility may also refer to:
* A measure of turbidity in water quality control
* Interferometric visibility, which quantifies interference contrast ...
light
Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 tera ...
, or a surface that absorbs light, such as black.
Human
vision
Vision, Visions, or The Vision may refer to:
Perception Optical perception
* Visual perception, the sense of sight
* Visual system, the physical mechanism of eyesight
* Computer vision, a field dealing with how computers can be made to gain un ...
is unable to distinguish
color
Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associ ...
s in conditions of very low
luminance
Luminance is a photometric measure of the luminous intensity per unit area of light travelling in a given direction. It describes the amount of light that passes through, is emitted from, or is reflected from a particular area, and falls withi ...
because the
hue
In color theory, hue is one of the main properties (called Color appearance model#Color appearance parameters, color appearance parameters) of a color, defined technically in the CIECAM02 model as "the degree to which a Stimulus (physiology ...
sensitive
photoreceptor cell
A photoreceptor cell is a specialized type of neuroepithelial cell found in the retina that is capable of visual phototransduction. The great biological importance of photoreceptors is that they convert light (visible electromagnetic radiatio ...
s on the
retina
The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then ...
are inactive when light levels are insufficient, in the range of visual perception referred to as
scotopic vision
In the study of human visual perception, scotopic vision (or scotopia) is the vision of the eye under low-light conditions. The term comes from Greek ''skotos'', meaning "darkness", and ''-opia'', meaning "a condition of sight". In the human eye, ...
.
The emotional response to darkness has generated
metaphor
A metaphor is a figure of speech that, for rhetorical effect, directly refers to one thing by mentioning another. It may provide (or obscure) clarity or identify hidden similarities between two different ideas. Metaphors are often compared wit ...
ical usages of the term in many cultures, often used to describe an unhappy or foreboding feeling.
Referring to a time of day,
complete darkness occurs when the
Sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
is more than 18° below the
horizon
The horizon is the apparent line that separates the surface of a celestial body from its sky when viewed from the perspective of an observer on or near the surface of the relevant body. This line divides all viewing directions based on whether i ...
, without the effects of
twilight
Twilight is light produced by sunlight scattering in the upper atmosphere, when the Sun is below the horizon, which illuminates the lower atmosphere and the Earth's surface. The word twilight can also refer to the periods of time when this il ...
on the
night sky
The night sky is the nighttime appearance of celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon.
Natural light sources in a night sky include ...
.
Scientific
Perception
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 the 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
A photon () is an elementary particle that is a quantum of the electromagnetic field, including electromagnetic radiation such as light and radio waves, and the force carrier for the electromagnetic force. Photons are massless, so they alway ...
, causing it to appear dim compared to other objects. For example, 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
Color (American English) or colour (British English) is the visual perceptual property deriving from the spectrum of light interacting with the photoreceptor cells of the eyes. Color categories and physical specifications of color are associ ...
. An object may appear dark, but it may be bright at a frequency that humans cannot perceive.
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
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
, like a human, enters a dark area, its
pupils
The pupil is a black hole located in the center of the iris of the eye that allows light to strike the retina.Cassin, B. and Solomon, S. (1990) ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company. It appears black ...
dilate, allowing more light to enter the eye and improving
night vision
Night vision is the ability to see in low-light conditions, either naturally with scotopic vision or through a night-vision device. Night vision requires both sufficient spectral range and sufficient intensity range. Humans have poor night vi ...
. Also, the light detecting cells in the human eye (
rods and cones
A photoreceptor cell is a specialized type of neuroepithelial cell found in the retina that is capable of visual phototransduction. The great biological importance of photoreceptors is that they convert light (visible electromagnetic radiati ...
) will regenerate more unbleached
rhodopsin
Rhodopsin, also known as visual purple, is a protein encoded by the RHO gene and a G-protein-coupled receptor (GPCR). It is the opsin of the rod cells in the retina and a light-sensitive receptor protein that triggers visual phototransduction ...
when adapting to darkness.
One scientific measure of darkness is the
Bortle scale
The Bortle scale (also known as the Bottle scale) is a nine-level numeric scale that measures the night sky's brightness of a particular location. It quantifies the astronomical observability of celestial objects and the interference caused by lig ...
, which indicates the night
sky's and stars' brightness at a particular location, and the observability of celestial objects at that location.
The material known as
Vantablack
Vantablack is a brand name for a class of super-black coatings with total hemispherical reflectances (THR) below 1.5% in the visible spectrum. The coatings were invented by Ben Jensen, who first publicly unveiled them in July 2014, and commercia ...
is one of the darkest substances known, absorbing up to 99.965% of visible light (at 663 nm if the light is perpendicular to the material), and was developed by Surrey NanoSystems in the United Kingdom.
The name is a compound of the acronym VANTA (vertically aligned nanotube arrays) and the color black.
Technical
The color of a
point
Point or points may refer to:
Places
* Point, Lewis, a peninsula in the Outer Hebrides, Scotland
* Point, Texas, a city in Rains County, Texas, United States
* Point, the NE tip and a ferry terminal of Lismore, Inner Hebrides, Scotland
* Point ...
, on a standard 24-bit
computer display
A computer monitor is an output device that displays information in pictorial or textual form. A discrete monitor comprises a visual display, support electronics, power supply, housing, electrical connectors, and external user controls.
The d ...
, 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
Artistic
Artists use darkness to emphasize and contrast the presence of light. Darkness can be used as a counterpoint to areas of lightness to create
leading lines and
voids
Void may refer to:
Science, engineering, and technology
* Void (astronomy), the spaces between galaxy filaments that contain no galaxies
* Void (composites), a pore that remains unoccupied in a composite material
* Void, synonym for vacuum, a s ...
. Such shapes draw the eye around areas of the painting. Shadows add depth and perspective to a painting. See
chiaroscuro
Chiaroscuro ( , ; ), in art, is the use of strong contrasts between light and dark, usually bold contrasts affecting a whole composition. It is also a technical term used by artists and art historians for the use of contrasts of light to achi ...
for a discussion of the uses of such contrasts in visual media.
Color
paints
Paint is any pigmented liquid, liquefiable, or solid mastic composition that, after application to a substrate in a thin layer, converts to a solid film. It is most commonly used to protect, color, or provide texture. Paint can be made in many ...
are mixed together to create darkness, because each color absorbs certain frequencies of light. Theoretically, mixing together the three
primary colors
A set of primary colors or primary colours (see spelling differences) consists of colorants or colored lights that can be mixed in varying amounts to produce a gamut of colors. This is the essential method used to create the perception of a bro ...
, or the three
secondary colors
A secondary color is a color made by mixing of two primary colors in a given color space.
Additive secondaries
Light (RGB)
For the human eye, good primary colors of light are red, green, and blue. Combining lights of these colors produces a ...
, will absorb all visible light and create black. In practice, it is difficult to prevent the mixture from taking on a brown tint.
Literature
As a poetic term in the
Western world
The Western world, also known as the West, primarily refers to the various nations and state (polity), states in the regions of Europe, North America, and Oceania. , darkness is used to connote the presence of shadows, evil, and foreboding, or in modern parlance, to connote that a story is grim, heavy, and/or depressing.
Religion
The first creation narrative in
Judaism
Judaism ( he, ''Yahăḏūṯ'') is an Abrahamic, monotheistic, and ethnic religion comprising the collective religious, cultural, and legal tradition and civilization of the Jewish people. It has its roots as an organized religion in the ...
and
Christianity
Christianity is an Abrahamic monotheistic religion based on the life and teachings of Jesus of Nazareth. It is the world's largest and most widespread religion with roughly 2.38 billion followers representing one-third of the global pop ...
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 God, darkness was considered "the second to last
plague
Plague or The Plague may refer to:
Agriculture, fauna, and medicine
*Plague (disease), a disease caused by ''Yersinia pestis''
* An epidemic of infectious disease (medical or agricultural)
* A pandemic caused by such a disease
* A swarm of pes ...
" (
Exodus
Exodus or the Exodus may refer to:
Religion
* Book of Exodus, second book of the Hebrew Torah and the Christian Bible
* The Exodus, the biblical story of the migration of the ancient Israelites from Egypt into Canaan
Historical events
* Ex ...
10:21), and the location of "weeping and gnashing of teeth" (
Matthew 8:12).
Erebus
In Greek mythology, Erebus (; grc, Ἔρεβος, Érebos, "deep darkness, shadow".), or Erebos, is the personification of darkness and one of the primordial deities. Hesiod's ''Theogony'' identifies him as one of the first five beings in exis ...
was a
primordial deity in
Greek mythology
A major branch of classical mythology, Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of Ancient Greek folklore. These stories concern the Cosmogony, origin and Cosmology#Metaphysical co ...
, representing the personification of darkness.
Philosophy
In
Chinese philosophy
Chinese philosophy originates in the Spring and Autumn period () and Warring States period (), during a period known as the "Hundred Schools of Thought", which was characterized by significant intellectual and cultural developmen ...
,
yin
Yin may refer to:
*the dark force in the yin and yang from traditional Chinese philosophy and medicine
*Yīn (surname) (), a Chinese surname
*Yǐn (surname) (), a Chinese surname
*Shang dynasty, also known as the Yin dynasty
**Yinxu or Yin, the S ...
is the complementary feminine part of the
taijitu
In Chinese philosophy, a ''taijitu'' () is a symbol or diagram () representing Taiji () in both its monist ('' wuji'') and its dualist (yin and yang) aspects. Such a diagram was first introduced by Neo-Confucian philosopher Zhou Dunyi (; 1017 ...
and is represented by a dark lobe.
Poetry
The use of darkness as a
rhetorical device
In rhetoric, a rhetorical device, persuasive device, or stylistic device is a technique that an author or speaker uses to convey to the listener or reader a meaning with the goal of persuading them towards considering a topic from a perspective, ...
has a long-standing tradition. William Shakespeare, working in the 16th and 17th centuries, made a character called the "prince of darkness" (
King Lear
''King Lear'' is a tragedy written by William Shakespeare.
It is based on the mythological Leir of Britain. King Lear, in preparation for his old age, divides his power and land between two of his daughters. He becomes destitute and insane an ...
: III, iv) and gave darkness jaws with which to devour love. (
A Midsummer Night's Dream
''A Midsummer Night's Dream'' is a comedy written by William Shakespeare 1595 or 1596. The play is set in Athens, and consists of several subplots that revolve around the marriage of Theseus and Hippolyta. One subplot involves a conflict amon ...
: I, i) Geoffrey Chaucer, a 14th-century Middle English writer of ''
The Canterbury Tales
''The Canterbury Tales'' ( enm, Tales of Caunterbury) is a collection of twenty-four stories that runs to over 17,000 lines written in Middle English by Geoffrey Chaucer between 1387 and 1400. It is widely regarded as Chaucer's ''Masterpiece, ...
'', wrote that knights must cast away the "workes of darkness". In ''
Divine Comedy
The ''Divine Comedy'' ( it, Divina Commedia ) is an Italian narrative poem by Dante Alighieri, begun 1308 and completed in around 1321, shortly before the author's death. It is widely considered the pre-eminent work in Italian literature and ...
'', Dante described hell as "solid darkness stain'd".
Language
In
Old English
Old English (, ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlement of Britain, Anglo ...
there were three words that could mean darkness: , and '. ' also meant "hiding-place" and became holster. ' meant "mist" and fell out of use like many
strong verbs. It is however still used in the
Dutch
Dutch commonly refers to:
* Something of, from, or related to the Netherlands
* Dutch people ()
* Dutch language ()
Dutch may also refer to:
Places
* Dutch, West Virginia, a community in the United States
* Pennsylvania Dutch Country
People E ...
saying "" which means secretly. ' meant "shadow" and remained in use. The word ''dark'' eventually evolved from the word '.
See also
*
Lightness
Lightness is a visual perception of the luminance (L) of an object. It is often judged relative to a similarly lit object. In colorimetry and color appearance models, lightness is a prediction of how an illuminated color will appear to a stan ...
*
Shadow
A shadow is a dark area where light from a light source is blocked by an opaque object. It occupies all of the three-dimensional volume behind an object with light in front of it. The cross section of a shadow is a two-dimensional silhouette, o ...
*
Theory of colours
''Theory of Colours'' (german: Zur Farbenlehre, links=no) is a book by Johann Wolfgang von Goethe about the poet's views on the nature of colours and how these are perceived by humans. It was published in German in 1810 and in English in 1840. ...
*
Nyctophobia
Fear of the dark is a common fear or phobia among children and, to a varying degree, adults. A fear of the dark does not always concern darkness itself; it can also be a fear of possible or imagined dangers concealed by darkness. Some degree of ...
References
External links
*
*
*
{{Goth subculture
Blindness