Color - Colours
Color is a
visual attribute of
things that results from the
light
they
emit or absorb or reflect. The
appearance of objects or light
sources described in terms of a person's
perception of their hue and
lightness or brightness and saturation. Did you know that the world's
favorite color is blue?
How do Colors make you Feel?
RGB
is an additive color model in which
red,
green and
blue light are added
together in various ways to reproduce a broad array of colors. The name of
the model comes from the initials of the three additive primary colors,
red, green and blue. The main purpose of the RGB color model is for the
sensing, representation and display of images in
electronic systems, such
as televisions and computers, though it has also been used in conventional
photography. Before the electronic age, the RGB color model already had a
solid theory behind it, based in human perception of colors.
CMYK vs RGB Info-Graph (image)
What is the difference between RGB and CMYK? (youtube)
Additive Color
is color created by
mixing a number of different light colors, with shades
of red, green, and blue being the most common primary colors used in
additive color system. Combining RGB = White Light.
CMYK
is a subtractive color model, used in color
printing, and is also used to
describe the printing process itself. CMYK refers to the four inks used in
some color printing:
cyan,
magenta,
yellow and key (
black). Though it
varies by print house, press operator, press manufacturer, and press run,
ink is typically applied in the order of the abbreviation.
Subtractive Color explains the mixing of a limited set of dyes, inks,
paint
pigments or natural colorants to create a wider range of colors,
each the result of partially or completely subtracting (that is,
absorbing) some wavelengths of light and not others. The color that a
surface displays depends on which parts of the
visible spectrum are not
absorbed and therefore remain visible. Subtractive color systems start
with light, presumably white light. Colored inks, paints, or filters
between the watchers and the light source or reflective surface subtract
wavelengths from the light, giving it color. If the incident light is
other than white, our visual mechanisms are able to compensate well, but
not perfectly, often giving a flawed impression of the "true" color of the
surface. Conversely, additive color systems start with darkness. Light
sources of various wavelengths are added in various proportions to produce
a range of colors. Usually, three primary colors are combined to stimulate
humans’ trichromatic color vision, sensed by the three types of cone cells
in the eye, giving an apparently full range. Combining RGB paint colors =
Black.
Pantone Colors
Matching System is largely a standardized color reproduction system. By
standardizing the colors, different manufacturers in different locations
can all refer to the Pantone system to make sure colors match without
direct contact with one another.
Chromatic
Color is a color that has
hue.
Hue is the quality of a color as determined
by its dominant wavelength.
Chromaticity is
an objective specification of the quality of a color regardless of its
luminance. Chromaticity consists of two independent parameters, often
specified as hue (h) and colorfulness (s), where the latter is
alternatively called saturation, chroma, intensity, or excitation purity.
This number of parameters follows from trichromacy of vision of most
humans, which is assumed by most models in color science.
Electromagnetic Spectrum
(visible spectrum - color spectrum) -
Structural Color
-
Luminescence (chemical
reactions) -
Prisms (colors in the light) -
Schlieren Optics
Rainbow
is a meteorological phenomenon that is caused by
reflection, refraction
and dispersion of light in
water droplets resulting in a
spectrum of light
appearing in the sky. It takes the form of a multicoloured arc. Rainbows
caused by
sunlight always appear in the section of sky directly opposite
the sun. Rainbows can be full circles. However, the observer normally sees
only an arc formed by illuminated droplets above the ground, and centred
on a line from the sun to the observer's eye. In a primary rainbow, the
arc shows
red on the outer part and violet on the inner side. This rainbow
is caused by
light being refracted when entering a droplet of water, then
reflected inside on the back of the droplet and refracted again when
leaving it. In a double rainbow, a
second arc is seen outside the primary
arc, and has the order of its colours reversed, with red on the inner side
of the arc.
Halos (ice).
This is Not a Rainbow (youtube)
-
The existence of the rainbow depends on the
conical photoreceptors in your
eyes. To animals without cones, the rainbow
does not exist.
You're Probably Wrong About Rainbows (youtube - Veritasium)
A rainbow is typically seen at a roughly 42 degree
angle from the observer's perspective. This is the angle at which
light refracts and
reflects within a raindrop, creating the rainbow effect.
Caustic Scattering Angle refers to the specific scattering angle at
which a concentration of scattered light occurs, forming a caustic,
usually happening when light rays converge after reflecting or
refracting off a
curved surface, like in the
phenomenon of a rainbow where the scattering angle at the rainbow's arc is
considered the caustic scattering angle.
Brewster's Angle
is an angle of incidence at which light with a particular
polarization is perfectly
transmitted through a transparent dielectric surface, with
no reflection. When unpolarized light
is incident at this
angle, the
light that is reflected from the surface is therefore perfectly
polarized.
She's A
Rainbow - The Rolling Stones - 1966 (youtube) -
She comes in colours everywhere, She combs her hair, She's like a
rainbow, Coming, colours in the air, Oh, everywhere, She comes in colours.
Moonbow
is a rainbow produced by moonlight rather than sunlight. Other than the
difference in
light source, its formation is exactly the same as for a
solar rainbow: It is caused by the
refraction of
light in many water droplets, such as a rain shower or a waterfall,
and is always positioned in the opposite part of the sky from the moon
relative to the observer.
Blue Skies:
Nitrogen and Oxygen scatter the blue and violet light in every direction
through a phenomenon called
Rayleigh scattering. That's what makes the sky blue. Blue light is
scattered more than the other colors because it travels as shorter,
smaller waves. This is why we see a blue sky most of the time. Short
wavelengths that scatter
across the sky correspond to the colors blue and violet, making the real
color of the sky a bluish purple. However, the cone cells in our eyes that
detect color aren't very sensitive to violet, so we see the sky as blue.
The sky looks blue because red, orange and yellow or
long wavelength light,
are absorbed more strongly than is blue or
short wavelength light, so it
is mostly the blue that gets returned.
Why are the clouds white? In
a cloud, sunlight is scattered by much larger water droplets. These
scatter all colors almost equally meaning that the sunlight continues to
remain white and so making the clouds appear white against the background
of the blue sky.
Refraction
is the
change in direction of
wave
propagation due to a change in its transmission medium or when passing
from one medium to another. The amount by which a propagating wave is
bent.
Propagation
are the ways in which waves travel.
Light Reflectance Value is a scale that determines the quantity of
visible and usable light
reflected by all directions and all wavelengths
when a surface is illuminated. Essentially, this scale is used to identify
how much light a color
reflects or absorbs. LRV is a measure of visible
and usable light that is reflected from a surface when illuminated by a
light source. The measurement is most commonly used by design
professionals, such as architectural color consultants, architects,
environmental graphic designers and interior designers. LRVs are
frequently reported on paint chips or
paint samples. The values are used
by lighting designers to determine the number and type of light fixtures
needed to provide proper lighting for interior spaces.
Glossy vs Matte.
Iridescence is the phenomenon of certain
surfaces that appear to
gradually change colour as the
angle of view or the
angle of illumination changes. Examples of iridescence include soap
bubbles, butterfly wings and seashells, as well as certain minerals. It is
often created by structural coloration (microstructures that interfere
with light). Pearlescence is a related effect where some or all of the
reflected light is white, where iridescent effects produce only other
colours. The term pearlescent is used to describe certain paint finishes,
usually in the automotive industry, which actually produce iridescent
effects.
Engineers make clear droplets produce iridescent colors.
Purkinje Effect
is the tendency for the peak luminance sensitivity of the eye to shift
toward the blue end of the color spectrum at low illumination levels as
part of dark adaptation. In consequence, reds will appear darker relative
to other colors as light levels decrease.
Partial Solar Eclipse.
Kaleidoscope is
an optical instrument with two or more reflecting surfaces tilted to each
other in an angle, so that one or more (parts of) objects on one end of
the mirrors are seen as a regular
symmetrical pattern when viewed from the other end, due to repeated
reflection. The reflectors (or mirrors) are usually enclosed in a tube,
often containing on one end a cell with loose, colored pieces of glass or
other transparent (and/or opaque) materials to be reflected into the
viewed pattern. Rotation of the cell causes motion of the materials,
resulting in an ever-changing view being presented.
World’s Most Visible Color.
Nano Meter 555 Midlayer with Motion Capture Markers is designed to
make you highly visible in any light condition anywhere on earth –
combining insights from experimental psychology, the mechanics of the
human eye and material technology, as well as tapping into the brain’s
pattern recognition system.
In daylight, the intense green colour replicates the wavelength of light
that the human eye is most sensitive to. At night, retroreflective
motion caption markers light up when hit by any passing light source,
creating a pattern that the eye can process as recognisably human in 0.25
seconds.
Blackest Black material to date that is made from
carbon
nanotubes. The new coating is
10 times darker than
other very black materials.
Vantablack 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).
Outer Space.
Ultra-White Paint is whiter than the
whitest paint currently available. Scientists in the US have developed a
paint significantly "whiter than the whitest paint currently available".
Tests carried out by researchers at Purdue University on their
"ultra-white" paint showed it reflected more than 98% of sunlight. Ways to
keep buildings cool with improved super white paints. The best performing
white paints currently available typically
reflect around 85% of incoming
solar radiation. The researchers examined replacing titanium oxide with
inexpensive and readily available ingredients such as barite, which is an
artist's pigment, and powered polytetrafluoroethylene, better known as
Teflon. These ingredients help paints reflect UV light. The team also made
further refinements to the paint's formula, including reducing the
concentration of polymer binders, which also absorb heat.
Contrast -
Shades -
Spatial Intelligence
(space and object awareness) -
Eyes (sight)
Color Depth
is either the number of
bits used to indicate the color of a single pixel, in a bitmapped
image or video frame buffer, or the number of bits used for each color
component of a single pixel.
Pixel is
a physical point in a raster image, or the smallest addressable element in
an all points addressable display device; so it is the smallest
controllable element of a picture represented on the screen. The address
of a pixel corresponds to its physical coordinates. LCD pixels are
manufactured in a two-dimensional grid, and are often represented using
dots or squares, but CRT pixels correspond to their timing mechanisms.
Each pixel is a sample of an original image; more samples typically
provide more accurate representations of the original. The intensity of
each pixel is variable. In color imaging systems, a color is typically
represented by three or four component intensities such as red, green, and
blue, or cyan, magenta, yellow, and black. In some contexts (such as
descriptions of camera sensors), the term pixel is used to refer to a
single scalar element of a multi-component representation (more precisely
called a photosite in the camera sensor context, although the neologism
sensel is sometimes used to describe the elements of a digital camera's
sensor), while in yet other contexts the term may be used to refer to the
set of component intensities for a spatial position, though this is more
accurately termed a sample. Drawing a distinction between pixels,
photosite and samples avoids confusion when describing color systems that
use chroma subsampling or cameras that use Bayer filter to produce color
components via upsampling. The word pixel is based on a contraction of pix
(from word "pictures", where it is shortened to "pics", and "cs" in "pics"
sounds like "x") and el (for "element"); similar formations with 'el'
include the words voxel, texel and maxel (for magnetic pixel).
Color Chart
is a flat, physical object that has many different color samples present.
They can be available as a one-page chart, or in the form of swatchbooks
or color-matching fans. Typically there are two different types of color
charts: Color reference charts are intended for
color comparisons and
measurements. Typical tasks for such charts are checking the color
reproduction of an imaging system, aiding in color management or visually
determining the hue of color. Examples are the IT8 and ColorChecker
charts. Color selection charts present a palette of available colors to
aid the selection of spot colors, process colors, paints, pens, crayons,
and so on – usually the colors are from a manufacturers product range.
Examples are the Pantone and RAL systems.
Color
Code is a system for
displaying information
by using different colors.
Color-Coding
refers to an algorithmic technique which is useful in the discovery of
network motifs.
Pattern
Recognition.
Color Wheel
is an abstract illustrative organization of color hues around a circle,
which shows the relationships between primary colors, secondary colors,
tertiary colors etc.
Primary Color is an additive set of colors used, like red, green and
blue. In a subtractive set of colors, mixing of pigments or dyes for
printing, the colors magenta, yellow and cyan are normally used. Primary
Color is a small, arbitrary set of pigmented physical media, lights or
purely abstract elements of a mathematical colorspace model. Distinct
colors from a larger gamut can be specified in terms of a mixture of
primary colors which facilitates technological applications such as
painting, electronic displays and printing.
Secondary Color
is a color made by mixing two primary colors in a given color space.
Color Therapy (meditation) -
Psychology of Color -
Color
Symbolism
Color Theory
is a body of practical guidance to color mixing and the visual effects of
a specific color combination. There are also definitions (or categories)
of colors based on the color wheel: primary color, secondary color and
tertiary color, which is a color made by mixing full saturation of one
primary color with half saturation of another primary color and none of a
third primary color, in a given color space such as RGB, CMYK (more
modern) or RYB (traditional).
Complementary Colors
are pairs of colors which, when combined, cancel each other out. This
means that when combined, they produce a grey-scale color like white or
black. When placed next to each other, they create the strongest contrast
for those particular two colors. Due to this striking color clash, the
term opposite colors is often considered more appropriate than
"complementary colors". Which pairs of colors are considered complementary
depends on the color theory one uses: Modern color theory uses either the
RGB additive color model or the CMY subtractive color model, and in these,
the complementary pairs are red–cyan, green–magenta, and blue–yellow. In
the traditional RYB color model, the complementary color pairs are red and
green, yellow and purple and blue and orange, though these pairings fail
the modern definition of complementary colors, as they produce a brown
color when combined. Opponent process theory suggests that the most
contrasting color pairs are red–green, and blue–yellow.
A team of
computer scientists and designers has developed
a tool to help people use color better in graphic design. The tool,
De-Stijl, uses powerful machine learning technology to suggest intuitive
colour palettes for novice designers and inexperienced users. The software
combines and improves on the functionalities of existing tools like Figma,
Pixlr, and Coolor, allowing users to select important theme colors and
quickly visualize how they’ll impact a design.
Roy G. Biv
is an
acronym (
abbreviation
or initials) for the sequence of hues commonly described as making up a
rainbow: red, orange, yellow, green, blue, indigo and violet.
Color Vision Testing
Tetrachromacy
is the condition of possessing four independent channels for conveying
color information, or possessing four types of cone cells in the eye.
Organisms with tetrachromacy are called tetrachromats. In tetrachromatic
organisms, the sensory color space is four-dimensional, meaning that to
match the sensory effect of arbitrarily chosen spectra of light within
their visible spectrum requires mixtures of at least four primary colors.
Tetrachromacy is demonstrated among several species of birds, fish,
amphibians, reptiles, insects and some mammals. It was the normal
condition of most mammals in the past; a genetic change made the majority
of species of this class eventually lose two of their four cones.
SMPTE Color Bars
is a television test pattern used where the NTSC video standard is
utilized, including countries in North America.
Why Do We See Color?
Waves -
Light - Prisms.
Negative is an image, usually on a strip or sheet of transparent
plastic film, in which the lightest areas of the
photographed subject appear
darkest and the darkest areas appear lightest. This reversed order occurs
because the extremely light-sensitive chemicals a camera film must use to
capture an image quickly enough for ordinary picture-taking are darkened,
rather than bleached, by exposure to light and subsequent
photographic processing. In the case of color negatives, the colors
are also reversed into their respective complementary colors. Typical
color negatives have an overall dull orange tint due to an automatic
color-masking feature that ultimately results in improved color
reproduction. Negatives are normally used to make positive prints on
photographic paper by projecting the negative onto the paper with a
photographic enlarger or making a
contact print.
The paper is also darkened in proportion to its exposure to light, so a
second reversal results which restores light and dark to their normal
order. Negatives were once commonly made on a thin sheet of glass rather
than a plastic film, and some of the earliest negatives were made on
paper. It is incorrect to call an image a negative solely because it is on
a transparent material. Transparent prints can be made by printing a
negative onto special positive film, as is done to make traditional motion
picture film prints for use in theaters. Some films used in cameras are
designed to be developed by
reversal processing, which produces the final positive, instead of a
negative, on the original film. Positives on film or glass are known as
transparencies or diapositives, and if mounted in small frames designed
for use in a slide projector or magnifying viewer they are commonly called
slides.
Videos about Colors
Light Darkness and Colours (youtube)
Video
About How Ink is Made (youtube)
Cracking the Colour Code (youtube)
Computer Color is Broken (youtube)
Experimental
video "Kingdom of Colors" that mixes geometric shapes and acrylic inks
(youtube)
Monitors (computers)
Monochrome is an image that is composed of one color or has values of
one color.
Monochromatic Color are all the colors (tones, tints and shades ) of a
single hue. Tints are achieved by adding white and shades and tones are
achieved by adding a darker color, grey or black. Monochromatic color
schemes provide opportunities in art and visual communications design as
they allow for a greater range of contrasting tones that can be used to
attract attention, create focus and support legibility. The use of a
monochromatic color provides a strong sense of visual cohesion and can
help support communication objectives through the use of connotative
color. The relative absence of hue contrast can be offset by variations in
tone and the addition of texture. Monochromatic in science means
consisting of a single wavelength of light or other radiation (lasers, for
example, usually produce monochromatic light), or having or appearing to
have only one color (in comparison to polychromatic). That means according
to science the true monochromatic images can be strictly created only of
shades of one color fading to black. However, monochromatic also has
another meaning similar to “boring” or “colorless” which sometimes leads
to creating a design composed from true monochromatic color shades (one
hue fading to black), and the colors created from the one hue but faded to
all wavelengths (to white). This is not monochromatic in the strictly
scientific meaning of the word.
Why are
tennis balls yellow? The International Tennis Federation undertook
a study that found that
yellow tennis balls
were easier for home viewers to see on their TV screens. An official 1972
ITF rule change required that all regulation balls have a uniform surface
and be white or yellow in color. Wimbledon continued to use the
traditional white ball, but eventually adopted yellow balls in 1986.
Tennis balls begin to lose their bounce as soon as the tennis ball can is
opened.
How We See Colors - What is Color
Did you ever look at a beautiful
painting or witness a gorgeous sunset and wonder, `How is it that I am able to
see that?' What enables us to see the light and experience such wonderful shades
of color during the course of our everyday lives? Some may take seeing for
granted, but if the process is looked at closely, you can see what a wonder it
really is. First Things First...
Pure white
light, such as sunlight, is composed of the visible colors. Sir Isaac
Newton discovered this in 1666 by passing a beam of light through a
prism. The
renowned English scientist was 23 years old at the time. He was made to stay
home from Cambridge University for over a year because the plague that was
sweeping Europe had closed it down. It was during this period that Newton
performed his famous spectrum experiments. To alleviate the boredom of
quarantine, he punched holes in the curtains of his darkened room to study the
effects of light passing through a prism. The light separated into the same
progression of colors found in the natural rainbow. Although he found an
infinite number of colors in this spectrum, Newton wanted to show that there
were just seven main colors, like the seven known planets and the seven musical
notes in the diatonic scale. He identified red, orange, yellow, green, blue,
indigo and violet. This was also in keeping with Aristotle's seven classes of
color which he thought were all mixes of black and white. Using a second prism,
Newton showed that each color in the spectrum is monochromatic--that is,
composed of a single, unique wavelength which can't be further separated into
other colors. Newton's experiments showed that light can be combined to form
different colors. For example, combining blue and yellow light produces a green
light that appears identical to the pure green found in a prism spectrum.
(Modern techniques, however, show these greens to be two very different colors.
Such color pairs are called metamers because they appear to be identical even
though they have different wavelengths.) Using two prisms, Newton found that
some color combinations produce pure white instead of colored light. In effect,
they complete each other when mixed. These pairs of colors are called complements. In this example you see that purple and yellow lights combine to
form white.
How do we see Color?
The
human eye and
brain together translate
light into
color. Light receptors within the eye transmit messages to the brain, which
produces the familiar sensations of color. Newton observed that color is not
inherent in objects. Rather, the surface of an object reflects some colors and
absorbs all the others. We perceive only the reflected colors. Thus, red is not
"in" an apple. The surface of the apple is reflecting the wavelengths we see as
red and absorbing all the rest. An object appears white when it reflects all
wavelengths and black when it absorbs them all. Red, green and blue are the
additive primary colors of the color spectrum. Combining balanced amounts of
red, green and blue lights also produces pure white. By varying the amount of
red, green and blue light, all of the colors in the visible spectrum can be
produced. Considered to be part of the brain itself, the retina is covered by
millions of light-sensitive cells, some shaped like rods and some like cones.
These receptors process the light into nerve impulses and pass them along to the
cortex of the brain via the optic nerve. Have you ever wondered why your
peripheral vision is less sharp and colorful than your front-on vision? It's
because of the rods and cones. Rods are most highly concentrated around the edge
of the retina. There are over 120 million of them in each eye. Rods transmit
mostly black and white information to the brain. As rods are more sensitive to
dim light than cones, you lose most color vision in dusky light and your
peripheral vision is less colorful. It is the rods that help your eyes adjust
when you enter a darkened room. Cones are concentrated in the middle of the
retina, with fewer on the periphery. Six million cones in each eye transmit the
higher levels of light intensity that create the sensation of color and visual
sharpness. There are three types of cone-shaped cells, each sensitive to the
long, medium or short wavelengths of light. These cells, working in combination
with connecting nerve cells, give the brain enough information to interpret and
name colors. The human eye can perceive more variations in warmer colors than
cooler ones. This is because almost 2/3 of the cones process the longer light
wavelengths (reds, oranges and yellows).About 8% of men and 1% of women have
some form of color impairment. Most people with color deficiencies aren't aware
that the colors they perceive as identical appear different to other people.
Most still perceive color, but certain colors are transmitted to the brain
differently. The most common impairment is red and green dichromatism which
causes red and green to appear indistinguishable. Other impairments affect other
color pairs. People with total color blindness are very rare. Birds, fish and
many other mammals perceive the full spectrum. Some insects, especially bees,
can see ultraviolet colors invisible to the human eye. In fact, color
camouflage, one of nature's favorite survival mechanisms, depends on the ability
of the predator to distinguish colors. The predator is expected to be fooled by
the color matching of the prey. Until recently, it was thought that dogs didn't
see any color at all. Recent studies now show, however, that dogs can
differentiate between red and blue and can even pick out subtle differences in
shades of blue and violet.
Deciphering how the brain encodes color and shape. Study reveals how
the brain processes the external world using overlapping visual circuits.
Scientists previously believed that the
visual system initially encodes shape and color with different sets of
neurons and then combines them much later. But a new study shows that
there are neurons that respond selectively to particular combinations of color and shape.
How does the brain turn waves of light into experiences of color?
Perceiving something -- anything -- in your surroundings is to become
aware of what your senses are detecting. Today, neuroscientists identify,
for the first time, brain-cell circuitry in fruit flies that converts raw
sensory signals into color perceptions that can guide behavior. Many of us
take for granted the rich colors we see every day, the red of a ripe
strawberry or the deep brown in a child's eyes. But those colors do not
exist outside of our brains. Colors are perceptions the brain constructs
as it makes sense of the longer and shorter wavelengths of light detected.
Among the hues these neurons respond to are those that people would
perceive as violet and others that correspond to ultraviolet wavelengths
(not detectable by humans). Detecting UV hues is important for the
survival of some creatures, such as bees and perhaps fruit flies; many
plants, for example, possess ultraviolet patterns that can help guide
insects to pollen.
Structural Coloration is the production of colour by micro or nano-structures
fine enough to interfere with visible light. Structural colouration is
responsible for the blues and greens of many animals, as well as for the
gold, silver, and some purple-pink colours. Structural coloration in
animals, and a few plants, is the production of colour by
microscopically structured surfaces fine
enough to interfere with visible light
instead of
pigments, although some structural coloration occurs in combination
with pigments. For example, peacock tail feathers are pigmented brown, but
their microscopic structure makes them also reflect blue, turquoise, and
green light, and they are often iridescent.
The brain has no problem recognizing objects in black-and-white images.
A study explains why the brain can robustly recognize images, even without
color. New research offers a possible explanation for how the brain learns
to identify both color and black-and-white images. The researchers found
evidence that early in life, when the retina is unable to process color
information, the brain learns to distinguish objects based on luminance,
rather than color. Even though the human visual system has sophisticated
machinery for processing color, the brain has no problem recognizing
objects in black-and-white images. A new study from MIT offers a possible
explanation for how the brain comes to be so adept at identifying both
color and color-degraded images.
Before the topics of
light and
color can
be explored, there must first be an understanding of
waves. Waves have high and
low points, and the distance between one of those highs and lows and the next is
called a
wavelength. Just how long that wave is will determine the amount of
energy that it has. For example, a long wave has a low amount of energy or low
frequency, and a short wave has a high amount of energy or high frequency. What
we see in a
rainbow, then, are the wavelengths of the visible colors. You see,
our sun emits its radiation in this visible range, which our eyes interpret as
the colors of the rainbow. These colors are identified as the
visible spectrum
and are often times remembered as
ROY G. BIV: red, orange, yellow, green, blue,
indigo, and violet.
Wave Travel - How are these
waves related to
light and
color? Light travels in the form of a wave. It is basically
photons (pieces of
energy or particles), and mostly moves as waves. White light, or the
light from
the
sun, is made of colors, and colors are different types of light recognized
by their own
wavelengths. Waves exist above and below the visible spectrum, too.
Such waves called radio, microwave, and infrared are below the red end of the
spectrum, and ultraviolet (UV), x-rays, and gamma rays are above the violet.
These cannot be seen by the human eye, and therefore constitute the "invisible"
spectrum. Together, the visible and invisible spectrums make up the
electromagnetic spectrum.
Light Transfer - There
are three things that can happen to a light wave. It can be
reflected, absorbed,
or transmitted. This is determined by the object that the wave hits, and that
will give it its color. For an object to be black, it means that all the
wavelengths of light hitting that object are
absorbed; no light is reflected.
Solid objects, for the most part, will reflect light, and transparent objects
will transmit light through them. To illustrate this last fact, place a glass of
red fruit juice on a table. Hold a piece of white paper on one side of the glass
and chances are, if the light in the room is right, you will see red on that
piece of paper. The light transmitted the red color of the juice onto the paper.
Color from Light -
Colors are in the Light (prisms).
The wavelengths of visible light are:
Violet: 380–450 nm (688–789 THz frequency), Blue: 450–495 nm., Green:
495–570 nm., Yellow: 570–590 nm., Orange: 590–620 nm., Red: 620–750 nm
(400–484 THz frequency).
The color of anything depends on the type of light sent to our eyes;
light is necessary if we are to have any
perception of color at all. An object is "colored," as stated above, because of
the light it reflects—all other colors are absorbed into that specific object.
So then, an apple appears red because it
reflects red light. White light from
the sun contains all the possible color variations. Yet, the human eye can only
respond to certain colors and wavelengths, and not everyone sees the same colors
or exact same shades of a color. We are capable of seeing color because our
eyes
have light and color-sensitive receptors. These receptors are called rods
(receptive to amounts of light) and cones (sensitive to colors). Being able to
see color is a sensation, just like smelling a pie fresh out of the oven or
tasting your favorite meal. Different foods smell and taste different to each
person, and likewise, no color is seen exactly the same by two people, because
each person's rods and cones vary.
Scientists discover a 100-year-old math error, changing how humans see
color.
Mapping words to colors. While the range of colors your eyes may
perceive extends beyond the words language provides,
languages around the globe are
remarkably similar in how they partition the space of colors into a
vocabulary. Yet differences exist. In a study examining 130 diverse
languages around the world, researchers developed an algorithm to infer
the communicative needs that different linguistic communities place on
colors. No language has words for all the blues of a wind-churned sea or
the greens and golds of a wildflower meadow in late summer. Globally,
different languages have divvied up the world of color using their own set
of labels, from just a few to dozens. The study relied on a robust dataset
known as the World Color Survey, collected more than 50 years ago by
anthropologist Brent Berlin and linguist Paul Kay. Traveling to 130
linguistic communities worldwide, Berlin and Kay presented native speakers
with the same 330 color chips. They found that even completely different
languages tended to group colors in roughly the same way. What's more,
when they asked speakers to identify the focal color of a particular named
color -- the "reddest red" or "greenest green" -- speakers' choices were
highly similar across languages. Substantial research followed, some of
which suggested that one major reason for the remarkable similarities
between languages' color vocabularies came down to physiology. "Languages
differ, cultures differ, but our eyes are the same," says Plotkin. But
another reason for the overarching similarities could be that humans,
regardless of what language they speak, are more interested in talking
about certain colors than others. The Penn team used data from the World
Color Survey on focal colors to work backwards, going from speakers'
observations of the reddest red or greenest green to infer the
communicative need associated with each of the 330 colors in the survey.
"What was really surprising was that we could use just those best-example
colors to say what those communicative needs would have been," says Twomey.
The researchers were able to use the second part of the World Color Survey
data, on how languages divided color, to validate that their inference
algorithm could predict the communicative needs of different languages.
Their analysis underscores findings from earlier research, that warm-hued
colors have a higher communicative need. "On average across languages, the
reds and yellows have 30-fold greater demand than other colors," Plotkin
says. "No one really cares about brownish greens, and pastels aren't super
well represented in communicative needs," Twomey adds. The researchers
also looked at existing data on fruit-eating primates with color vision
systems like our own. These primates tend to eat ripe fruit with colors
that line up almost precisely with the places in the color spectrum with
high communicative need. "Fruits are a way for a plant to spread its
seeds, hitching a ride with the animals that eat them. Fruit-producing
plants likely evolved to stand out to these animals. The relationship with
the colors of ripe fruit tells us that communicative needs are likely
related to the colors that stand out to us the most," says Twomey. "To be
clear, this doesn't say that we have the communicative needs we have
because we need to communicate about fruit specifically." The team's
algorithm could predict not only the similarities but also the differences
between languages. While an emphasis on reds and yellows was universal,
certain languages also had high communicative needs for blues, while
greens turned up as important in other languages. The research team found
that some of these differences were associated with biogeography and
distance. Cultures that shared similar ecoregions were more similar in
their communicative needs around colors, perhaps owing to plants or
animals in that region that were important for food or other uses. "Now
that we have inferred how often people want to talk about certain colors
today, we can take a phylogeny of languages and try to infer what people
were talking about 500 or 1,000 years ago. What historical events coincide
with changes in our needs to talk about colors?" Plotkin says. "There is
tons of work still to be done here." Such questions will demand unique
collaborations like the one undergirded by MindCORE, a campus hub for
study of human intelligence and behavior which enabled this work.
"Inherently interdisciplinary questions like the ones we tackle in our
paper together can be challenging to work on precisely because it takes a
team of experts from different fields to answer them," Twomey says. "So I
feel very fortunate to have had MindCORE's support here at Penn to
assemble exactly the right team for this problem."
Pigment - Paint
Pigment is a material
that changes the color of
reflected or
transmitted light as the result of
wavelength-selective
absorption. This physical process differs from
fluorescence, phosphorescence, and other forms of
luminescence, in which a
material
emits light. Pigments have
molecules, and molecules either
absorb
certain wavelengths of light or
reflect certain wavelengths of light, and
if a
pigment reflects a certain wavelength of light, then that is what
color you will see. For
objects that have no pigments, like animals, then
the
shape and size of its surface either absorbs certain wavelengths of
light or reflects certain wavelengths of light, and if the
surface
reflects a certain wavelength of light, then that is what color you will
see.
Blue has a short wavelength and
red has a longer wavelength and yellow and green
is in between red and blue.
Harvard’s Pigment Library.
Skin Color -
Eye Color
Color Balance is
the global adjustment of the intensities of the colors (typically red,
green, and blue primary colors). An important goal of this adjustment is
to render specific colors – particularly neutral colors like white or grey
– correctly. Hence, the general method is sometimes called gray balance,
neutral balance, or
white balance. Color
balance changes the overall mixture of colors in an image and is used for
color correction. Generalized versions of color balance are used to
correct colors other than neutrals or to deliberately change them for
effect. White balance is one of the most common kinds of balancing, and is
when colors are adjusted to make a white object (such as a piece of paper
or a wall) appear white and not a shade of any other colour.
White balance or WB is the process of
removing unrealistic color casts, so that objects which appear white in
person are rendered white in your photo. Proper camera white balance has
to take into account the "color temperature" of a light source, which
refers to the relative warmth or coolness of white light.
Photopigment are
unstable pigments that undergo a chemical change when they
absorb light.
The term is generally applied to the non-protein chromophore moiety of photosensitive
chromoproteins, such as the
pigments involved in
Photosynthesis and photoreception. In medical
terminology, "photopigment" commonly refers to the photoreceptor proteins
of the
retina.
Chromophore is the part of a
molecule responsible for its color. The
color that is seen by our eyes is the one not absorbed within a certain
wavelength spectrum of visible
light. The chromophore is a region in the
molecule where the energy difference between two separate molecular
orbitals falls within the range of the
visible
spectrum. Visible light that hits the chromophore can thus be absorbed
by exciting an
electron
from its ground state into an excited state. In biological molecules that
serve to capture or detect light energy, the chromophore is the moiety
that causes a conformational change of the molecule when hit by light.
Fluorescence.
Animals are capable of changing their colors with varying degrees of
transformation. This may be a very gradual (shedding of fur or feathers)
seasonal
camouflage, occurring only
twice a year. In other animals more rapid changes may be a form of active
camouflage, or of signaling. Palaeontologists have discovered remarkable
new evidence that pterosaurs, the flying relatives of dinosaurs, were
able to control the color of their feathers using melanin pigments.
Dye is a
colored substance that has an affinity to the substrate to which it is
being applied. The dye is generally applied in an aqueous solution, and
may require a mordant to improve the fastness of the dye on the fiber.
Both dyes and pigments are colored, because they absorb only some
wavelengths of visible light. Dyes are usually
soluble in water whereas pigments are
insoluble. Some dyes can
be rendered insoluble with the addition of salt to produce a lake pigment.
Printing.
Ink is a
liquid or paste that
contains
pigments or
dyes and is used to color a
surface to produce an image, text, or design. Ink is used for
drawing or
writing with a
pen,
brush, or quill. Thicker inks,
in paste form, are used extensively in letterpress and lithographic
printing. Ink can be a complex medium, composed of solvents, pigments,
dyes, resins, lubricants, solubilizers, surfactants, particulate matter,
fluorescents, and other materials. The components of inks serve many
purposes; the ink's carrier, colorants, and other additives affect the
flow and thickness of the ink and its dry appearance. In 2011 worldwide
consumption of printing inks generated revenues of more than 20 billion US
dollars. Demand by traditional print media is shrinking, on the other hand
more and more printing inks are consumed for packaging's.
Paint is any pigmented
liquid, liquefiable, or 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 to objects. Paint can be made
or purchased in many colors—and in many different types, such as
watercolor, synthetic, etc. Paint is typically stored, sold, and applied
as a liquid, but most types dry into a solid.
Oil Paint is a type
of slow-drying paint that consists of particles of pigment suspended in a
drying oil, commonly linseed oil. The viscosity of the paint may be
modified by the addition of a solvent such as turpentine or white spirit,
and varnish may be added to increase the glossiness of the dried oil paint
film. Oil paints have been used in Europe since the 12th century for
simple decoration, but were not widely adopted as an
artistic medium until
the early 15th century. Common modern applications of oil paint are in
finishing and protection of wood in buildings and exposed metal structures
such as ships and bridges. Its hard-wearing properties and luminous colors
make it desirable for both interior and exterior use on wood and metal.
Due to its slow-drying properties, it has recently been used in
paint-on-glass animation. Thickness of coat has considerable bearing on
time required for drying: thin coats of oil paint dry relatively quickly.
Oil Painting
is the process of painting with pigments with a medium of drying oil as
the binder.
Drying Oil is an oil that hardens to a tough, solid film after a
period of exposure to air. The oil hardens through a chemical reaction in
which the components crosslink (and hence, polymerize) by the action of
oxygen (not through the evaporation of water or other solvents). Drying
oils are a key component of oil paint and some varnishes. Some commonly
used drying oils include linseed oil, tung oil, poppy seed oil, perilla
oil, and walnut oil. Their use has declined over the past several decades,
as they have been replaced by alkyd resins and other binders. Since
oxidation is the key to curing in these oils, those that are susceptible
to chemical drying are often unsuitable for cooking, and are also highly
susceptible to becoming rancid through autoxidation, the process by which
fatty foods develop off-flavors. Rags, cloth, and paper saturated with
drying oils may combust spontaneously (ignite) after a few hours as heat
is released during the oxidation process.
Colors Appearance Changes when near certain Colors - Contrast
Contrast is the opposition or
dissimilarity
of things that are
compared.
The act of distinguishing by
comparing differences. A
conceptual
separation or
distinction. The perceptual effect of the
juxtaposition of
very different colors. Put in opposition to show or emphasize
differences.
To show differences when compared; be different.
Contrast is the difference in luminance or colour that makes an object
(or its representation in an image or display) distinguishable. In visual
perception of the real
world, contrast is determined by the difference in the colour and
brightness of the object and other objects within the
same field of view.
The human visual system is
more sensitive to contrast than absolute
luminance; we can
perceive the world similarly regardless of the huge
changes in illumination over the day or from place to place. The maximum
contrast of an image is the contrast ratio or dynamic range.
Context.
Shade is
relative darkness caused by
light
rays being intercepted by an opaque body. A quality of a given color that
differs slightly from another color. Pass from one quality such as color
to another by a slight degree. A slight amount or degree of difference. A
subtle difference in meaning, opinion or attitude.
Black and
White are just different
shades of the same color. Shade can also be a protective covering that
protects something from direct sunlight.
Shade is the blocking of sunlight (in particular direct sunshine) by
any object, and also the
shadow created by
that object. Shade also consists of the colors grey, black, white, etc. It
may refer to blocking of sunlight by a roof, a tree, an umbrella, a window
shade or blind, curtains, or other objects.
Tints and Shades is a mixture of a color with
white, which increases lightness, while a shade is a mixture with
black, which increases darkness. Both
processes affect the resulting color mixture's relative saturation. A tone
is produced either by mixing a color with grey, or by both tinting and
shading. Mixing a color with any neutral color (including black, gray, and
white) reduces the chroma, or colorfulness, while the hue (the relative
mixture of red, green, blue, etc. depending on the colorspace) remains
unchanged.
Nonlinear is when some parts of the image have changed in brightness
to a different degree than others, or some parts of the image have become
brighter while others have become dimmer. Typically, changing the
intensity of light with which a scene is lit causes a linear change in the
brightness of different parts of the image. The figure below shows an
example of two images with a linear brightness change.
Linear means that two different light
signals (or of any other nature, in general) coming from two different
points of the object do not interfere with each other. The resulting image
of two emitting points is equal to the addition of the images that would
arise by measuring the two points separately.
#unfamiliar -
Imagery -
Mental Imagery.
Underwater Color
Loss (youtube) - The longest wavelengths, with the lowest energy, are
absorbed first. Red is the first to be absorbed, followed by orange &
yellow. The colors disappear underwater in the same order as they appear
in the color spectrum. Even water at 5ft depth will have a noticeable loss
of red. Longer wavelengths—such as red, orange, and yellow—are absorbed
within about the first 50 meters of the ocean. The shorter
wavelengths—such as green, blue, and violet— are absorbed less and are
able to reach deeper into the water. Blue light is least absorbed by water
molecules and reaches a depth of about 200 meters.
Gyroid
is an infinitely connected triply periodic minimal surface. Contains
neither straight lines nor planar symmetries. The gyroid separates space
into two oppositely congruent labyrinths of passages.
The Color Factor
- The impact that a color has depends on a combination of three factors: hue,
saturation, and luminance. Hue simply means the actual shade or color,
saturation is just how pure the hue is, and luminance is what is described when
we say that a color is either light or dark.
Color Complements
- Complementing colors also have to be considered if you are seriously
pondering color combinations. They highly contrast each other, and when placed
side by side, enhance the color of the other. Color complements are on opposite
ends of the color wheel; they also happen to have drastically different
wavelengths.
Color Trouble
-
Some people have trouble discerning colors, along with their shades and luminance. Color
blindness is a color perception problem whose most common ailment is a red-green
deficiency. This means that there is a lack of red or green photopigments and
people have difficulty making out colors that are based on the `red to green'
ratio. It is estimated that about 7% of all males are color blind, while
only .4% of women are affected. This is because the defect is linked to the
X-chromosome, of which males only have one, so there is less chance of it being
naturally corrected by the genes.
"Shadowing" Light and Color
-
Orthogonal Colors -
All of us have the potential to see light and colors "in a different
Light,"
so to say—even if we aren't color blind. Trace a ray of light from a point on a
solid object to a light source. If the ray of light hits another object before
you get to the light source, the point is in shadow. A shadow, present in an
area where there is less light, must be opposite a light source. The light,
object, and shadow will all be in a line. This is because light moves in
straight lines. Shadows are caused by objects blocking light from a bright
source. Materials may block some (translucent), all (opaque), or none
(transparent) of the light hitting them. We can see that shadow influences the
light that we are able to see, but we should also know now that this means the
colors of objects will be altered as well. Since color depends on the light
that we see, if some, all, or none of that light is blocked, some, all, or none
of the colors will be changed. Shading makes colors appear darker, since the
luminance (darkness or lightness) is altered. Since the sun's light contains all
the color possibilities, changed light will change colors as well.
Orthogonal is having a set of mutually
perpendicular axes; meeting at right angles. Statistically unrelated. Not
pertinent to the matter under consideration.
How Colors Affect Behaviors - Color Psychology
Color Psychology is the study of
colors in relation to human behavior.
It aims to determine how color affects our day to day decisions and our
perceptions. Certain colors are known to have definite behavior-altering
capabilities. Bright primary and secondary colors will attract the
children, while softer colors will attract their parents and grandparents.
And our personal and
cultural associations affect our experience of color. At about 5-months old,
children can see colors with their still-developing vision, though
distinguishing bright colors comes easier to them. As children age, they
continue to be drawn to brighter colors. Color has also been known to
affect their moods and behavior.
Yellow
revolves around sunshine. It evokes feelings of happiness, positivity,
optimism, and summer but also of deceit and warning.
Orange represents creativity, adventure,
enthusiasm, success, and balance. Pink color meaning revolves around
femininity, playfulness, immaturity and unconditional love.
Green is highly connected to nature and
money. Growth, fertility, health, and generosity are some of the positive
color meanings for the color. The color meaning for green also carries
some negative associations such as envy. If you’re in the health or
fitness niche, you might choose to add more green to your online store.
Blue color meaning ties closely to the sea
and the sky. Stability, harmony, peace, calm and trust are just some of
the feelings your customer may feel about your brand when you integrate
the color blue into your branding. Conversely, blue can also carry some
negative color meanings such as depression and can bring about a sense of
coldness.
Grey represents neutrality and
balance. Its color meaning likely comes from being the shade between white
and black. However, grey does carry some negative connotations,
particularly when it comes to depression and loss. Its absence of color
makes it dull. Red color meaning is associated with excitement, passion,
danger, energy, and action.
Black color
meaning is symbolic of mystery, power, elegance, and sophistication. In
contrast, the color meaning can also evoke emotions such as sadness and
anger.
Brown is an earthy color. After all,
it’s the color of earth, wood and stone. So naturally, color psychology
highlights that the color meaning for brown relates to comfort, security
and a down to earth nature.
Purple is
connected to power, nobility, luxury, wisdom, and spirituality. But avoid
using the color too much as it can cause feelings of frustration. Some
perceive its overuse as arrogant.
White
showcases innocence, goodness, cleanliness, and humility.
Colors Associations. Yellow,
orange and red are associated with the heat of sun and fire; blue, green and
violet with the coolness of leaves, sea and the sky.
Warm colors seem closer to
the viewer than cool colors, but
vivid cool colors can overwhelm light and
subtle warm colors. Using warm colors for foreground and cool colors for
background enhances the perception of depth. Although red, yellow and orange are
in general considered high-arousal colors and blue, green and most violets are
low-arousal hues, the brilliance, darkness and lightness of a color can alter
the
psychological message. While a light blue-green appears to be tranquil, wet
and cool, a brilliant turquoise, often associated with a lush tropical ocean
setting, will be more exciting to the eye. The psychological association of a
color is often more meaningful than the
visual experience. Colors act upon the
body as well as the mind. Red has been shown to stimulate the senses and raise
the blood pressure, while blue has the opposite effect and calms the mind.
People will actually gamble more and make riskier bets when seated under a red
light as opposed to a blue light. That's why Las Vegas is the city of red neon.
For most people, one of the first decisions of the day concerns color harmony.
What am I going to Wear? This question is answered not only by choosing a style
and fabric appropriate to the season, but by making the right color choices. Whether you're designing a new kitchen, wrapping a
present or creating a bar chart, the colors you choose greatly affect your final
results. How often have you caught your breath at the sight of a flowerbed in
full bloom? Most likely the gardener has arranged the
flowers according to their
color for extra vibrancy. Have you ever seen a movie in which a coordinated
color scheme helps the film create a world unto itself? With a little knowledge
of good color relationships, you can make colors work better for you in your
business graphics and other applications. Color is light and light is energy.
Scientists have found that actual physiological changes take place in human
beings when they are exposed to certain colors. Colors can stimulate, excite,
depress, tranquilize, increase appetite and create a feeling of warmth or
coolness. This is known as
chromodynamics. An executive for a paint company
received complaints from workers in a blue office that the office was too cold.
When the offices were painted a warm peach, the sweaters came off even though
the
temperature had not changed. The illusions discussed below will show you
that sometimes combinations of colors can deceive the viewer, sometimes in ways
that work to your advantage. They can also cause unfortunate effects in your
graphics, so be sure to watch out for these little traps. Sometimes colors
affect each other in unexpected ways. For example, most colors, when placed next
to their complements, produce vibrating, electric effects. Other colors, in the
right combinations, seem quite different from what you'd expect. The most
striking color illusions are those where identical colors, when surrounded by
different backgrounds, appear to be different from each other. In a related
effect, different colors can appear to be the same color when surrounded by
certain backgrounds. When you look at a colored object, your brain determines
its color in the context of the surrounding colors. In this picture, the two
bows are the same color, but because the surrounding areas are strikingly
different in contrast, it seems to our eyes that they are different. Keep this
effect in mind when creating graphics where color matching is critical. If you
attempt to match your corporation's official colors, you may find that even if
you achieve an exact match, it may look wrong in context. In the same way that
one color can appear different in different surroundings, two similar colors may
appear to be identical under some conditions. Even though the two symbols are
actually slightly different tones, the contrasting backgrounds cause our brains
to think that they are the same color. This effect is harder to control, but be
aware of it because it can affect your graphics in hidden ways. The feeling you
get when looking at bright complementary colors next to each other is a
vibrating or pulsing effect. It seems that the colors are pulling away from each
other. It's caused by an effect called color fatiguing. When one color strikes a
portion of the retina long enough, the optic nerve begins sending confused
signals to the brain. This confusion is intensified by the
complementaries.
Mixing brilliant complementary colors gets attention, but it should be used with
restraint. The effect is disconcerting and can make your eyes feel like they've
been shaken around. If you want to use complementary colors without causing
discomfort, you can outline each of the colors with a thin neutral white, gray
or black line. The outlines separate the two colors, which helps your brain keep
them separated. When two very similar colors touch in an image, both colors
appear to wash out and become indistinct. This is because the borders between
the colors are difficult to distinguish and your brain blurs the colors
together. If you outline each of the colors with a thin neutral white, gray or
black line, the colors become easier to distinguish. This is called the stained
glass technique and is a way to reduce this blurring of the colors.
Color Therapy (meditation) -
Sadness Impairs Color Perception -
Consciousness
Color Combinations like Red, Yellow and White give people certain feelings.
Logos -
Marketing.
Colors evoke similar feelings around the world. A detailed survey of
4,598 participants from 30 nations over six continents. Participants were
asked to fill out an online questionnaire, which involved assigning up to
20 emotions to twelve different color terms.
Chromophobia is the irrational fear of, or aversion to, colors.
Colorimetry is the science and technology used to quantify and
describe physically the human color perception.
Goethe on the Psychology of Color and Emotion.
Green is
a color between blue and yellow in the
color
spectrum that is similar to the color of fresh grass or any of various leafy
plants or their leaves and stems eaten as vegetables. By far the largest
contributor to green in nature is chlorophyll, the chemical by which
plants
photosynthesize and convert sunlight into chemical energy. Many
creatures have adapted to their green environments by taking on a green
hue themselves as camouflage. Green is evoked by light which has a
dominant
wavelength
of roughly 495–570 nm.
Physical
effects to your body in the presence of green. Your pituitary gland is stimulated. Your muscles
are more relaxed, and your blood histamine levels increase, which leads to
a decrease in allergy symptoms and dilated blood vessels, aiding in
smoother muscle contractions. In short, green is calming,
stress-relieving, and–a bit paradoxically–invigorating. It’s been shown to
improve reading ability and creativity.
Green also means sustainable
and less wasteful or polluting.
Going green
is when someone or something makes changes to help protect the
environment, or reduces waste or pollution.
Get
the green light is get approval to move ahead or proceed with a
project or task.
Green corn is the young, tender
ears of Indian corn.
Green thumb or Green
fingers is an unusual ability to make plants grow.
Green room is a room in a theater or studio where performers can
relax before or after appearances.
Greenback
is a legal-tender note issued by the United States government.
Greener pastures is something newer or
better or perceived to be better.
Green with envy
is being jealous or envious.
Greenhorn is a
novice, trainee, beginner.
Green around the gills
is marked by a pale, sickly, or nauseated appearance.
Turn green is to look pale and ill as if
you are going to vomit.
Color
Symbolism in
art and
anthropology refers to the
use of color as a symbol in various
cultures. There is great diversity in the use of colors and their
associations between cultures and even within the same culture in
different time periods. The same color may have very different
associations within the same culture at any time. For example, red is
often used for stop signs or danger. At the same time, red is also
frequently used in association with romance, e.g. with Valentine's Day.
White variously signifies purity, innocence, wisdom or death. Blue has
similarly diverse meanings. Diversity in color symbolism occurs because
color meanings and symbolism occur on an individual, cultural and
universal basis. Color symbolism is also context-dependent and influenced
by changes over time.
Symbolic representations of religious concepts or
articles may include a specific color with which the concept or object is
associated. There is evidence to suggest that colors have been used for
this purpose as early as 90,000 BC. Extensive associations for each color
are listed in their respective articles. Arthur Bliss wrote A Colour
Symphony in 1922, depicting in each movement a particular color and its
associated
symbolism.
Holi is a
Hindu spring festival celebrated in India and Nepal, also known as the
"festival of colours" or the "festival of love". The festival signifies
the victory of good over evil, the arrival of spring, end of winter, and
for many a festive day to meet others, play and laugh, forget and forgive,
and repair broken relationships. It is also celebrated as a thanksgiving
for a good harvest. It lasts for a night and a day, starting on the
evening of the Purnima (Full Moon day) falling in the Vikram Samvat Hindu
Calendar month of Phalgun, which falls somewhere between the end of
February and the middle of March in the Gregorian calendar. The first
evening is known as Holika Dahan or Chhoti Holi and the following day as
Holi, Rangwali Holi, Dhuleti, Dhulandi, or Phagwah.
Theory of Colours
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. Published in 1810, it
contains detailed descriptions of phenomena such as coloured shadows,
refraction, and chromatic aberration.
Associating Colors with Vowels?
Coloring Vision, Appetite, and Mood:
If you think colors are pretty to look at but have no real impact on people, think again. Certain colors
are known to have definite behavior-altering capabilities. Some colors or
combinations of them irritate eyes and cause headaches. For example, bright
yellows—either on walls or as the background on a computer screen—are the most
bothersome colors and are not calming or relaxing in any way. Bright colors
reflect more light, so yellow over-stimulates our eyes, causing strain and even
irritability. You wouldn't ever want to paint a baby's room yellow, but you
could certainly use it on important street signs to attract attention. Other
colors can alter how or what we eat. Blue is known to curb appetites. Why is
this so? Blue food doesn't exist in nature, with the exception of the blueberry.
There are no blue vegetables, and hopefully, if you encountered a blue meat, you
certainly wouldn't eat it. Because of this natural color deficiency, there is no
automatic appetite response to anything blue. There are colors that can put us
in a better mood, too. Green is the most restful color for the eye. It has the
power to soothe and comfort. Studies have even shown that people who work in
surroundings that are green experience fewer headaches, stomach aches, and other
signs of sickness or fatigue.
Out of Sight!
Besides being pretty to look at, colors and the light they come from really do have the power to impact
people in many ways. Along with the aesthetics of light and color, there is
real science behind each and every sight we see. Each flash or ray of light,
each shade of color that light makes visible, and each time our eyes receive the
messages to see them, we are reminded of a special relationship—one that is
often overlooked because we simply take seeing for granted. We miraculously
experience a bright, vivid world because of the workings of our eyes, the
wonders of light, and the brilliance of color.
Artistic and creative businesses such as
florists, gift shops and designers, should use unusual color combinations
that reflect their creative flair. These may include combinations of
purple and variations of purple such as plum, magenta and other pinks,
pale blue, and yellow. Pleasing color combinations rather than discordant
combinations are best as they are a preview of your work.
Fashion boutiques and beauty salons aimed
at the female market should choose from softer feminine colors such as
pastels, pinks, coral, soft blue or green, turquoise or light purple. In
choosing the best colors for this type of retail business you must first
take into account the target market. For the female market choose pastels
and pinks, coral, turquoise or light purple. For the male market blue is
always a good choice as the majority of men love all types of blue.
Men's clothing stores need to choose colors
that will attract their male customers, but they also need to take into
account that often it is women who do the buying for their partners, sons
or fathers. Blue is a color that is attractive to the majority of people,
including both genders and all age groups, so it is a good choice for
these stores. Adding some red or blue to the color scheme will add energy
to the blue.
Restaurants, bistros, cafes and
coffee shops, should use warm colors ranging from red to orange.
Colors from the red range are stimulating to the appetite and encourage
people to eat more. Colors from the orange range are stimulating to social
communication and conversation as well as encouraging people to eat more.
Upper-class restaurants can use softer versions of orange, such as peach,
apricot, terracotta or coral to encourage appetite and conversation or
deeper reds for elegance and appetite stimulation. Combine with some form
of green, aubergine or cream for a stylish and elegant effect. Hotels and
bars are wise to use some form of green to encourage people to drink more.
Combined with a soft muted orange to encourage conversation and social
communication.
Entertainment businesses
need colors that exude fun and happiness. Yellow as part of your color
scheme is appropriate for this type of retail business. If your business
is to stimulate activity with participants then red will encourage this.
If social interaction is your purpose, then orange is the best choice.
Purples, mauves and pastel colors will create the right atmosphere for
fantasy type businesses.
Green is
stimulating to thirst, so it is appropriate to use it in situations where
a restaurant relies on beverages as a major part of its custom. Some green
combined with a variation of either red or orange is appropriate for all
food outlets. Green also helps staff tolerate a noisy environment.
Yellow is a happy and playful color but it
can create anxiety. If you want your customers to be in and out quickly,
and to make quick purchases, then yellow will help. Otherwise use it in
small amounts as it can agitate and stress some people.
Blue will suggest you are honest and
trustworthy and have a calming effect on your customers. Blue will also
entice your customers to linger for longer in your store and help to
retain loyal customers. It is a color favoured by most people.
Red should be used in small doses in retail
businesses. It can cause aggression and anger if used in large amounts so
use it as an accent color to add energy, passion and excitement.
A Pop of Color on Public Spaces. Baltimore-based artists Jessie
Unterhalter and Katey Truhn found a way to enhance people’s lives through
art by adding visual playfulness to
public spaces.
Use of Color in Architecture and Urban Design.
Color Matters: The Impact of Color.
Color
Scheme is the choice of colors used in design for a range of media.
For example, the "Achromatic" use of a white background with black text is
an example of a basic and commonly default color scheme in web design.
Color schemes are used to create style and appeal. Colors that create an
aesthetic feeling when used together will commonly accompany each other in
color schemes. A basic color scheme will use two colors that look
appealing together. More advanced color schemes involve several related
colors in "Analogous" combination, for example, text with such colors as
red, yellow, and orange arranged together on a black background in a
magazine article. The addition of light blue creates an "Accented
Analogous" color scheme.
Color
Depth is either the number of bits used to indicate the color of a
single pixel, in a bitmapped image or video framebuffer, or the number of
bits used for each color component of a single pixel.
Color Characteristics - Color Attributes
There are literally millions of colors! But fortunately, they can be divided into just
a few color families. And every color can be described in terms of having three
main attributes: hue, saturation and brightness.
Hue is identified as the
color family or color name (such as red, green, purple). Hue is directly linked
to the color's wavelength.
Saturation, also called "chroma," is a measure
of the purity of a color or how sharp or dull the color appears.
Brightness, also called "luminance" or "value," is the shade (darkness) or tint
(lightness) of a color. Areas of an evenly colored object in direct light have
higher brightness than areas in shadow.
Color Classifications
- The concept of the color wheel was invented when Sir Isaac Newton bent the
color spectrum into a circle. Since then, the color wheel has been used as a
tool for understanding color relationships and creating harmonious color
schemes. The color wheel clearly shows which colors are warm and cool,
complementary, split complementary and analogous. The diagrams in the following
pages demonstrate each of these concepts.
Cool colors range from blue to
violet, the half of the color wheel with shorter wavelengths. Cool colors have a
calming effect. They are frequently used for backgrounds to set off smaller
areas of warm colors. Used together, cool colors can look clean and crisp,
implying status and calm. However, it is important to note that usage of bright
cool colors generates more excitement than light, medium or dark cool colors.
Warm colors range from red to yellow, essentially the half of the color
wheel corresponding to the longer wavelengths. Warm colors are active,
attention-grabbing and aggressive. They stimulate the emotions, motivate and
seem to come forward off the screen or page.
Complementary colors lie
opposite each other on the color wheel. They complete or enhance each other.
Impressionist painters in the 19th century often placed dots of pure
complementary pigment on a color's surface to make the color come alive. While
the dots weren't apparent to the viewer, the color appeared especially vibrant.
When mixed together equally, subtractive complements, such as paints, should
theoretically produce black or gray. In practice, the pigments are never perfect
and the result is a muddy brown instead.
Using complementary colors in an
image is quite pleasing to the eye. The colors seem to belong together. The most
effective use of complements is to let one of them dominate by giving it a
bigger area or a fuller saturation, while using the other as
an accent.
Split complements (also known as contrasting colors or triads)
lie on either side of a color's complement on the color wheel. These colors
offer many of the same benefits as complementary colors, but the effect is more
subtle. As two of the colors will be very similar, using fully saturated
colors may be too strong. Dilute the saturation by using darker shades or
lighter tints to draw the colors together.
Analogous color schemes use
colors that are adjacent on the color wheel and so have similar hues. For
example, blues, blue-greens and greens are analogous. When using analogous
colors in a presentation, make one color dominant to avoid confusion and use the
other colors as accents.
A monochromatic color scheme uses a single hue
with variations in the saturation and brightness only. Such a color scheme
produces simple images with no discord. However, if you plan to use
monochromatic colors for your business graphics, make sure that you have the
contrast necessary to make clear distinctions for the audience and to emphasize
the important points. This is also important for achromatic graphics, which use
white, black and shades of gray.
Achromatic color schemes have no color.
They use black, white and shades of gray to represent colors. It may be that
while your graphics will be presented in color, you'll need to produce
black-and-white handouts. If so, review each handout carefully for legibility,
as colors don't always translate to grayscales as expected. If a grayscaled
image isn't clear enough, consider replacing blocks of color with patterns to
increase legibility.
Color HarmonyIn art as well as music, harmony comes
from a pleasing arrangement of the parts. The science of color harmony traces
its roots back to 1893 when Chevreul's "The Principles of Harmony and Contrast
of Colors," was published.
The science of color harmony categorizes
colors and determines harmonious groupings, such as complements, split
complements, triads and analogies. Where science becomes art is in knowing how
to use these colors, in what proportions and in what order. In color and music,
contrasts intensify each other. Complementary colors bring out the attributes of
each other. White becomes brighter on a black background, blue enhances the
warmth of orange; opposite hues are especially attention-getting. This hue
contrast can cause tension in the image, if you are using fully saturated
colors. Complementary colors can be brought into harmony by reducing the
saturation or by mixing a little of each color with the other. This tension is
at its strongest when large areas of complementary colors touch. Leonardo di
Vinci was the first to study this effect, known as simultaneous contrast. For
the most part, it's visually disturbing and should be avoided. Separating large
areas of complementary colors with a thin line of neutral white, gray or black will diminish the effect.
Varying the saturation
or brightness of a color can cause light and dark contrasts. By simply working
with complementary and analogous colors, a harmonious color scheme can easily be
created. Pay attention to the saturation and brightness of the colors to prevent
unexpected contrasts or to create intentional ones. If two colors are equal in
saturation and proportions, the dominant color will be the one whose brightness
is furthest from the background's. Similarly, if two colors have identical brightnesses, the dominant
color will be the one whose saturation deviates more from that of the
background.
Color Models - When you ask children to tell you the names
of all the colors, they'll know red, blue, yellow and a few more. A more
sophisticated adult will be able to name periwinkle, mauve, fuchsia and maybe
another hundred. There are, however, thousands of regularly used colors and
millions more that can be distinguished by the human eye. To give a name to each
of them would be impossible, so scientists have devised various ways of
assigning numeric values to colors. These systems are called color models, and
they provide precise methods for naming and reproducing exact colors. Some are
based on the optical components of the colors and others are based on how people
"feel" colors are related to each other.
RGB
Model - (Red, Green, Blue) - In the RGB system, the red, green and blue dots are assigned
brightness values along some scale, for example 0 to 255, where 0 is dark and
255 is bright. By listing the three values for the red, green and blue
phosphors, you can specify the exact color that will be mixed. Additive colors
get lighter when mixed. As each component of light is mixed in, the combination
becomes a new color. Red, green and blue are the three additive primaries. You
can mix any color of light with different combinations of the additive
primaries. When you mix all three together in balanced amounts, you get white.
These three primaries are the basis of the additive color model. It's called the
RGB model, and it's usually used to create color on your computer display as
well as other electronic devices. By mixing together various amounts of red,
green and blue light, you can make almost any color. The RGB color space is a
multi-colored cube with different points showing what colors different mixtures
of red, green, and blue make. Television screens and computer monitors make
their colors by mixing red, green and blue lights. A monitor or television
screen mixes a color by illuminating tiny dots of red, green and blue phosphors
with an electron gun located at the back of the monitor. By illuminating each of
the dots to a different brightness, the monitor creates different colors. The
next several pages have descriptions of the major color models and some
experiments to help you visualize how they work. Because the RGB model is only capable of producing a certain range, or gamut, of
colors, there are some colors that cannot be reproduced accurately by a
computer monitor. The number of colors visible on a monitor is further reduced
by the limitations of the video hardware in the computer, which may display
anywhere from just black and white up to 16.7 million colors. Cyan, magenta
and yellow are the three subtractive primaries. Nearly any color can be produced
with different combinations of these three colors. When you mix all three
together in equal amounts, you get a near black. These three primaries are the
basis of the subtractive color model. That's why it's called the CMY model. A
close relative of the CMY model, called CMYK, is commonly used by printers and
some software.
CMYK Model - (Cyan, Magenta, Yellow, Black)
-
Many computer printers and traditional "four-color" printing presses use the CMYK
model. In the CMYK model, by using cyan, magenta, yellow and black inks or
paints, you can mix nearly any color.
In theory, you can mix any
reflective color by mixing a combination of cyan, magenta and yellow. In the
real world, however, the inks that printers use are not perfect. This becomes
most obvious when you mix all three to make black. The color that results is
muddy brown, due to impurities in the inks. That's why printers use black ink to
get the best results. Subtractive colors get darker when mixed. Each of the
mixed paints or inks absorbs different components of the light. If the right
combination of paints is mixed together, all of the components of light are
absorbed and the result is a near black.
When preparing a color image for
printing, the prepress operator makes four separation plates. Each plate is for
one of the four colors of ink in the CMYK
model. When all four plates are aligned and printed on top of each other, the
inks will combine to simulate the proper colors. This method is referred to as
"process color" (or "four-color") printing.
HSL Model (Hue, Saturation, Luminance) - The HSL model is very similar to the RGB model.
In fact, when they're expressed mathematically, they're identical. The
difference lies in how colors are expressed numerically. The hue determines
which basic color it is. Red, green, blue, yellow, orange, etc. are different hues. Saturation and luminance tell more about the variations of these basic
colors. Saturation is the vividness (or "purity") of the color, i.e., how much
of the color's complement is mixed in. Finally, luminance refers to the
"whiteness" of the color. It may also be termed "brightness," "value" or
"intensity."
Other models related to the HSL
model are the HSB (Hue, Saturation, Brightness) and HSI (Hue, Saturation,
Intensity) models. These terms are all similar but not interchangeable.
CIE Model (Commision Internationale l'eclairage) -
The CIE model is a more subjective description than the others. In 1931, the Commision Internationale l'Eclairage
tested many people and found that the sensitivity of the receptors in the eye
caused certain colors to be associated with others. The CIE color space includes
all visible colors, whether or not they can be defined in the RGB or CMYK
models. Computer printers and other devices for displaying color have practical
limitations that prevent them from making ALL of the visible colors. The colors
that they CAN create are collectively called the color gamut. The CIE model is
useful in part because a printer's color gamut can be drawn on the CIE color
space showing what colors cannot be printed. Other color models closely related
to CIE are UCS (Uniform Color Space), CIELAB and CIELUV.
Pantone® Color Reference Systems
-
The PANTONE MATCHING SYSTEM® is a solid color
communication system based on the visual matching of individual, pre-mixed
colors. The PANTONE MATCHING SYSTEM is a series of books with thousands of
precisely printed colors alongside printers' formulas for mixing those colors.
The PANTONE MATCHING SYSTEM is used by artists and commercial printers to
select, specify and match colors very precisely.
Many logos are created with specific PANTONE Colors that can be very closely
reproduced. By using PANTONE Colors, designers can be confident that their
output will match their expectations. The original PANTONE MATCHING SYSTEM
included 504 colors and has since been expanded to include 1,012 colors along
with their printing ink formulations. For four-color (CMYK) printing, the
PANTONE Process Color System® specifies more than 3,000 colors and shows the
screen percentages for printing. Recently, as computers have been used more
extensively for business and professional graphics, software users have begun to
specify their colors with the PANTONE MATCHING SYSTEM and the PANTONE Process
Color System. More and more software products have been licensed by Pantone,
Inc. to ensure a greater degree of consistency throughout the industry.
Hexachrome® - More recently, Pantone has introduced a revolutionary,
patented six-color process printing system called Hexachrome. By providing an enhanced set of Cyan,
Magenta, Yellow and Black, plus the addition of PANTONE Hexachrome® Orange and
PANTONE Hexachrome Green, the color gamut for reproducing printed photographic
images and simulated spot colors has been substantially increased. One of the
inherent short-comings of printing with CMYK (commercially and/or digital
printers) is that the resultant color gamut is relatively restricted, resulting
in a considerable loss of color from the original artwork. In fact the
four-color (CMYK) gamut can only reproduce 50% of the spot/solid PANTONE
MATCHING SYSTEM Colors. With Hexachrome, you can now reproduce over 90% of these
spot/solid colors, and get a substantially enhanced reproduction of the
photograhic images. how can we reproduce color?
Colorful graphics get the
attention and the professional admiration of your viewers, but producing color
graphics on the computer used to be so time consuming and expensive that it was
only used for professionally published work. Now that the technology has become
accessible to even casual users you may find yourself expected to produce
colorful handouts, slides or reports on a regular basis. For some purposes, it
is sufficient to be able to display your graphics on screen and show them
informally. In a meeting, you may need to print out a few copies as handouts.
Occasionally you'll need to publish hundreds or thousands of copies to distribute more widely.
Color Coding
The Color Wheel - Although most of the time we don't even think about color
consciously, some people think about and plan colors very seriously. Whether it
be a dress maker color coordinating fabrics, a painter imagining the perfect
eye-pleasing portrait, or someone simply redoing their living room, a color
wheel can be very useful. A color wheel is a tool that helps artists and others
learn and visualize color relationships; it shows how primary colors can combine
to create many other colors.
Pigment Color
-
An artist's traditional color wheel has 12
colors: 3 primary, 3 secondary, and 6 tertiary. Some materials let certain
colors pass through them, and absorb other colors. These materials are called
dyes or pigments. The primary colors of pigment are red, blue, and yellow.
Mixing these primary colors of pigment gives us the three secondary colors:
red+blue=violet, red+yellow=orange, and yellow+blue=green. Then, the primary
colors mixed with the secondary give us the tertiary. They are: red- violet,
red-orange, yellow-orange, yellow-green, blue-green, and blue-violet.
Light Color
-
The primary colors of light are red, blue, and green, and
the secondary are yellow, cyan, and magenta. It is very important to know that
mixing pigment and mixing light are very different. Red and green paint, for
example, make brown paint, but red and green light make yellow light. When beams
of light are mixed without any absorption, an additive process occurs. The more
we mix the beams, the closer they get to being white light. However, when we put
light through a color filter, a subtractive process occurs. Some wavelengths of
light are being absorbed (subtracted) and we only see the wavelengths that are
selectively given off. The Additive and Subtractive Models are explained further
below.
Additive Color
-
As stated previously, the primary colors of light are red, blue, and green. These occur in the Additive
Color (RGB) Model, so named because black is the base and light is "added" to
eventually get to white, which is all of the colors together. Additive colors
are seen in televisions, nature, and the computer screen you are looking at
right now. Amazingly enough, colors are perceived in our eyes and brains by a
three-color code; three different particles in the retina are sensitive to—you
guessed it—red, blue, and green. Just as any color of the spectrum can be
made by mixing the three primary colors, so do our own eyes discern the various
colors by sensing different wavelengths with these three receptors.
Subtractive Color
-
The Subtractive Color (CMYK or CMY) Model is used for printed publications. There
are only four colors that offset the printing process. The subtractive colors
are also the secondary colors in light: cyan, magenta, and yellow. Black is used
in the subtractive model as well, because cyan, magenta, and yellow make more of
a dark gray than pure black when they are combined. In the Subtractive model,
light reflected off a surface is what the surface doesn't absorb.
Color Displays
No matter how you intend to show your computer graphics, you'll see them first on a
computer monitor.. All monitors have
limitations that you should know about before you begin. Most color computer
monitors work on the same principle as a television. The screen is composed of
phosphor dots that are illuminated from behind. On a color monitor, red, green
and blue dots are distributed evenly. These dots are illuminated to
different brightnesses to mix the
different colors you see on the screen. If you look very closely, you can see
these individual dots. Most computer display systems are made up of two
components: the monitor and a video adapter card that resides in the computer
itself. The quality of the display is affected by both the monitor and the video
card. Besides the size of the screen, computer display systems have two primary
features that determine the quality of the image: resolution and color depth.
Resolution determines the fineness of detail on the screen. The color depth
determines how much control you have over the coloring of your graphics. The
video card determines how many colors can be displayed by the monitor. Since the
colors are created by mixing different brightness levels for each of the three
color dots, a monitor can only mix as many colors as the number of brightness
combinations it can make. The number of colors that can be displayed by a video
card is called its color depth and is usually specified in bits per pixel. Color
depths in commercial video cards range from black and white (one bit) to over 16
million colors (24 bits). Of course, the human eye can't distinguish that many
colors, so these higher-end displays are more powerful than most people need.
When designing on the desktop, your first concern is to assure that you are
seeing color on your monitor as accurately as possible. The PANTONE Personal
Color Calibrator™ software gives you the ability to set the manufacturer's
standard profile for a specific brand and model of monitor, but further lets you
set up and save your personal preference for red/green/blue acuity, brightness,
contrast and lighting conditions. In many cases, the number of colors in an
image will exceed the capabilities of the device used to display the image. For
example, it may be necessary to present a 256-color image on a 16-color display
system, or to print a scanned photograph on a low-end dot-matrix printer. In
situations such as these, the image is automatically simplified to reduce the
number of colors. This process is referred to as color reduction. As a typical
user, you don't need to worry about doing the color reduction. That's usually
done for you by the computer system or your software application. Color
reduction takes its toll on the quality of your displayed images, however, and
you will probably notice these effects in your work. Color reduction typically
uses a technique called dithering. In the same way that the monitor simulates
individual colors with its red, green and blue dots, even more colors can be
simulated by arranging individual pixels. This technique creates a coarse image
which will only look good at a distance. Over the years, a wide variety of
dithering methods (or algorithms) have been developed and implemented for use in
image processing. The choice of any particular method depends on the exact
nature of the image, the display system and the desired results. Dithering
usually creates various distracting patterns (called artifacts or moirŽ
patterns) in the image. Some dither patterns produce better gradations and
shading than others, but may require more processing time and memory. When
designing for Web site displays, you can reduce the effects of dithering and
provide more consistent color on different monitors if you use the 216
"internet-safe," non-dithering colors. Pantone's ColorWeb® and ColorWeb® Pro
software packages help you select and incorporate these colors in the popular
Web authoring software programs.
Printing
When Printing Color Photos at home remember there are some important variables to be aware of.
1: Photo Paper. Each type of
paper reacts differently (glossy, matte, soft gloss) you could even have a bad
batch of photo paper so don't always assume that it's the printer, software or
the photo itself. -
Photo Paper (amazon).
2: Printer Settings. You could even have a bad ink cartridge or the wrong color profile.
-
Printers.
3: Software that you use to Print
and Edit the photo. -
Photo Editing Software (amazon)
4: Scanner settings if the photo is scanned.
Scanners (amazon) -
Neatco.
5: Photograph
Colors and Monitor Colors: The Photo may
also have slight color variations that you don't notice on your PC Monitor
because the
Monitor is
not always adjusted properly or calibrated properly and may not see the certain
colors correctly. If you send a color to someone else they might see a
different shade of that color on their monitor compared to what you see on your
monitor. And what colors you see on your monitor might not be the same colors
printed.
Monitor Color
Calibration -
How To
Calibrate Your Monitor for Color
Calibration of LCD, CRT, Projector & Notebook Monitor Displays (amazon)
ColorMunki (amazon)
-
Monitor Test Images
Dots Per
Inch or
DPI is a measure of spatial printing
or video dot density, in particular the number of individual dots that can
be placed in a line within the span of 1 inch (2.54 cm). 96 px for every inch on your
Monitor Screen.
100×100 pixel image
that is printed in a 1cm square has a resolution of 100 pixels per centimeter (ppcm).
Pixel
is a physical point in a raster image, or the smallest addressable element
in an all points addressable display device; so it is the smallest
controllable element of a picture represented on the screen. The address
of a pixel corresponds to its physical coordinates. LCD pixels are
manufactured in a two-dimensional grid, and are often represented using
dots or squares, but CRT pixels correspond to their timing mechanisms.
Pixels
Per Inch are measurements of the pixel density (resolution) of an electronic
image device, such as a computer monitor or television display, or image
digitizing device such as a camera or image scanner. Horizontal and
vertical density are usually the same, as most devices have square pixels,
but differ on devices that have non-square pixels.
Resolution is the ability of a
microscope or
telescope to measure the
angular separation of images that are close together. Analysis into
clear-cut components. Resolution in computing is the number of pixels per
square inch on a computer-generated display; the greater the resolution,
the better the picture. Resolution can also mean a statement that solves a
problem or explains how to solve the problem. A decision to do something
or to behave in a certain manner.
Resolution Types
(wiki).
Optical Resolution describes the ability of an imaging system to
resolve detail in the object that is being imaged. An imaging system may
have many individual components including a lens and recording and display
components. Each of these contributes to the optical resolution of the
system, as will the environment in which the imaging is done.
Super-Resolution Microscopy is a term that gathers several techniques,
which allow images to be taken with a higher resolution than the one
imposed by the diffraction limit. Due to the
diffraction of light,
the resolution in conventional light microscopy is limited. A
diffraction-limited microscope with numerical aperture N.A. and light with
wavelength λ reaches a lateral resolution of d = λ/(2 N.A.) - a similar
formalism can be followed for the axial resolution (along the optical
axis, z-resolution, depth resolution). The resolution for a standard
optical microscope in the visible light spectrum is about 200 nm laterally
and 600 nm axially. Experimentally, the attained resolution can be
measured from the full width at half maximum (FWHM) of the point spread
function (PSF) using images of point-like objects. Although the resolving
power of a microscope is not well defined, it is generally considered that
a super-resolution microscopy technique offers a resolution better than
the one stipulated by Abbe. Super-resolution imaging techniques rely on
the near-field (photon tunneling microscopy as well as those that utilize
the Pendry Superlens and near field scanning optical microscopy) or on the
far-field. Among the latter are techniques that improve the resolution
only modestly (up to about a factor of two) beyond the diffraction-limit
like the confocal microscope (with closed pinhole), or confocal microscopy
aided with computational methods such as deconvolution or detector-based
pixel reassignment (e.g. re-scan microscopy, pixel reassignment), the 4Pi
microscope, and also structured illumination microscopy technologies like
SIM and SMI. There are two major groups of methods for super-resolution
microscopy in the far-field that can improve the resolution with a much
larger factor: Deterministic super-resolution: The most commonly used
emitters in biological microscopy, fluorophores, show a nonlinear response
to excitation, and this nonlinear response can be exploited to enhance
resolution. These methods include STED, GSD, RESOLFT and SSIM. Stochastic
super-resolution: The chemical complexity of many molecular light sources
gives them a complex temporal behavior, which can be used to make several
close-by fluorophores emit light at separate times and thereby become
resolvable in time. These methods include Super-resolution optical
fluctuation imaging (SOFI) and all single-molecule localization methods
(SMLM) such as SPDM, SPDMphymod, PALM, FPALM, STORM and dSTORM.
Display Resolution or display modes of a digital television, computer
monitor or display device is the number of distinct pixels in each
dimension that can be displayed. It can be an ambiguous term especially as
the displayed resolution is controlled by different factors in cathode ray
tube (CRT) displays, flat-panel displays (including liquid-crystal
displays) and projection displays using fixed picture-element (pixel)
arrays.
Image Resolution
is the detail an image holds. The term applies to raster
digital images,
film images, and other types of images. Higher resolution means more image
detail.
Digital Image
is a numeric representation of (normally binary) a two-dimensional image.
Depending on whether the image resolution is fixed, it may be of vector or
raster type. By itself, the term "digital image" usually refers to raster
images or bitmapped images.
Binary
Image is a digital image that has only two possible values for each pixel.
Typically, the two colors used for a binary image are black and white,
though any two colors can be used. The color used for the object(s) in the
image is the foreground color while the rest of the image is the
background color. In the document-scanning industry, this is often
referred to as "bi-tonal".
What is an Image?
(photography)
There are many variables that could have effects on the quality of your finished
printed photo. So experiment with the
settings of your printer, Software and also try different paper. Most important
make one change at a time and write down all your changes and findings so that
you can learn what settings and paper make the best photographs. When achieved
you can print out some really great photos at home and have more control over
the quality and price, providing you have a nice
printer of course that specializes in
photo printing.
Note: In Photoshop you can mouse over a color to see its
color balance (under the Info tool bar) if you need to match it with a
particular color.
If your Color is off on your Printed Photo you
have a few things you need to check:
1: Make sure your monitor
screen colors are correct and calibrated so that you can see the colors in your
photo as they are.
2: Print a color test page
(under printer options or maintenance) If colors are correct save your color
test page for future reference to compare to a new test page if suspecting a
problem.
3: Check printer cartridge
(sometimes you can get a bad cartridge, if you do, switch cartridge's to see if
that's the problem. You might have to try your deep cleaning option for your
printer head, (under printer maintenance) and print out a color test page to
make sure each color looks OK. Make sure printer head is aligned (under
printer maintenance).
4: It's better to adjust your photo in
Adobe Photoshop Elements 7
or in other photo editing software instead of using your printer settings to get
desired effects. Printer settings should mostly be adjusted for Paper type, size
(portrait or landscape), extra fine and photo.
5: If you do have a nice
Photo Editing Software then you should be able to mouse over the color in
question and see the color balance in the photo information tab in both
RGB & CMYK. Then you can compare that color to
known colors for verification.
6: For optimum results make sure your photo is close to
300dpi before printing, especially if you're
resizing the photo.
7: Even though "PictBridge"
(camera to printer technology) is convenient, it's is always better to see your
photo full screen on a 15" Monitor before printing. This way you're sure you're
printing a good photo the way you want it without wasting paper & ink.
8: Print
your photos using software like
Quarkxpress for best results.
Desktop Printing: If you want to print your graphics on paper but only need a few copies, you
need a color
printer for your computer. The cost and quality of these printers
has been improving dramatically since they were first introduced, leaving you
with quite a few choices. The four primary printer technologies for producing
color output vary in cost, resolution, color depth and paper requirements.
Individual printers also vary in quality, speed, reliability and lifespan.Pantone has several software packages that can help you manage and
control color on the desktop. PANTONE ColorDrive® and PANTONE ColorReady™ are
designed to work with popular graphic design programs like Quark XPress™,
Photoshop®, Illustrator® and the like, and also provide more accurate output on
a wide range of desktop printers. The company also offers PANTONE OFFICECOLOR
ASSISTANT™ which allows the reduction and use of PANTONE MATCHING SYSTEM® Colors
in Microsoft® Word, Excel and Powerpoint to assist the business manager in
producing more attractive presentations and reports.
Ink -
Paint -
Pigments
Lithography is a method of printing originally based on the
immiscibility of
oil and water. The printing is
from a stone (lithographic limestone) or a metal plate with a smooth
surface. It was invented in 1796 by German author and actor Alois
Senefelder as a cheap method of publishing theatrical works. Lithography
can be used to print text or artwork onto paper or other suitable
material.
Digital Printing refers to methods of printing from a digital-based
image directly to a variety of media. It usually refers to professional
printing where small-run jobs from desktop publishing and other digital
sources are printed using large-format and/or high-volume laser or inkjet
printers. Digital printing has a higher cost per page than more
traditional offset printing methods, but this price is usually offset by
avoiding the cost of all the technical steps required to make printing
plates. It also allows for on-demand printing, short turnaround time, and
even a modification of the image (variable data) used for each impression.
The savings in labor and the ever-increasing capability of digital presses
means that digital printing is reaching the point where it can match or
supersede offset printing technology's ability to produce larger print
runs of several thousand sheets at a low price.
UV Pinting or
Ultraviolet Printing is a form of
digital printing that uses ultra-violet lights to dry or cure ink as
it is printed. The UV ink is printed directly onto the substrate and when
the inks are exposed to UV light they turn from a liquid, to a solid
instantly.
Commercial Printing: If you need to produce hundreds or thousands of copies
of your work, you will need to take your output to a commercial printer for a
large press run. This process is somewhat demanding and expensive, but is
the only way to make large numbers of copies. Commercial printing requires quite
a bit of prepress work for each job. Producing camera-ready originals is
somewhat technical, so most printing houses have full-time prepress technicians
who can do some or all of the work for you, depending on your experience and budget. When you are deciding what type of
printing to do, speed, cost per copy and quality of the output are some of the
deciding factors. The printer's estimator can advise you about the choices
available. There are two different ways color can be applied to paper in color
printing: spot color and process color. Spot color is a method of applying a
premixed color of ink directly to the page. Process color applies four or more
standard ink colors (the basic four are cyan, magenta, yellow and black) in very
fine screens so that many thousands of colors are created. Spot color is usually
used when a few exact colors are needed. Process color is more useful for
printing photographs, paintings and very complex colored images. In some cases,
both spot color and process color can be used on the same document. For example,
a company brochure may include color photos (process color) and a corporate logo
(spot color). Spot color applies a premixed ink to the page. This color is
usually identified by a color system such as the PANTONE MATCHING SYSTEM. Spot
color is useful for documents that require only a few colors, such as
newsletters, brochures and stationery. Spot color is also used to match specific
colors very closely. The cost of printing color documents is related to the
number of ink colors used. As process color requires four or more inks, spot
color can be cheaper if you use fewer than four colors. Spot color also has the
advantage of printing a wider range of clean, bright colors. Look around you for
an example of spot color printing. If a color seems smooth and even no matter
how closely you look, it's probably printed with spot color. Process color is a
method used to create thousands of colors using four or more standard inks. The
colors used in four-color process are the three subtractive primaries (cyan,
magenta and yellow) plus black. The original image is separated into its cyan,
yellow, magenta and black components. A film is made for each separation and
then a plate is produced from the film. The paper is run through the four
stations of a four-color press to accept layers of ink from each plate. When all
four colors are printed together, the illusion of continuous color is
complete. More recently Pantone has patented a unique six-color process printing
technology called Hexachrome®. By incorporating an enhaced set of cyan, magenta,
yellow and black and adding PANTONE Hexachrome® Orange and PANTONE Hexachrome
Green, the reproduction of photograhpic imagery can be substantially enriched.
Additionally, nearby all the solid PANTONE MATCHING SYSTEM Colors can be
accurately simulated, thus eliminating the need to supplement the image
reproduction with several spot colors, scanning, designing, seperating, proofing
and printing. Take a look around you for a full-color newspaper, book or
magazine. If you look very closely at a color photograph, you can make out the
halftone dots of the four inks. If you are printing in process color, your image
will require a plate for each of the cyan, magenta, yellow and black inks. As
each color of ink used is laid down on the paper individually, a different plate
must be created for each ink. Spot colors each require their own plate as well.
Separations can be created in quite a few different ways. You may be asked to
provide a full color printout to be optically separated. Your image will either
be scanned or run through a separator, which separates the image using filters.
On the other hand, you may be asked to provide a disk containing the graphics
file. An imagesetter, which is essentially a very high-resolution printer, will
create the separations directly from the graphics file. Halftoning is the most
common of the many ways printers create different shades of color from just one
ink. A finely etched screen is used when making each plate. This screen changes
the darker and lighter areas of the original into areas of larger and smaller
dots. When printed, the larger dots will appear darker than the smaller dots,
due to greater ink coverage. When multiple colors of ink are printed together,
the different apparent shades will combine to simulate far more colors than are
actually used. Halftoning is done with a very fine screen when printing on
glossy paper and for higher quality documents. Coarser screens are used for
rough paper such as newsprint. Newspapers use coarse screens, so it's fairly
easy to make out the individual dots in newspaper photographs. The fineness of
halftone screens is determined by the number of lines of halftone dots per inch.
This is called the "lines per inch" or the LPI. Lithography means
"stone-writing." Invented in 1799 by Aloys Senefelder in Germany, this process
relies on the fact that water and grease repel each other. A lithograph stone is
prepared by drawing the image to be printed on polished limestone with a greasy
crayon. In commercial offset lithography, the lithography stone is replaced by
thin metal plate that wraps around a printing cylinder. The imaging areas on the
plate are water repellent and accept ink, while the non-imaging areas accept
water and reject ink. The ink is offset from the metal plate onto a rubber
blanket and then onto the paper, preventing excess wear of the plate. Offset
printing is well-suited for color printing, because a typical press can handle
six colors with a single pass, including four process and two spot colors, or
six-color Hexachrome. WHY WYS IS NOT WYGA common acronym in computer graphics is
WYSIWYG. It stands for "What you see is what you get." Unfortunately, a common
problem in reproducing color graphics is that what you see on the screen is not
what you get when you print.
Printing
History.
Bleed is printing that goes
beyond the edge
of where the sheet will be trimmed. In other words, the bleed is the area
to be trimmed off. The bleed is the part on the side of a document that
gives the printer a small amount of space to account for movement of the
paper, and design inconsistencies. Artwork and background colors often
extend into the bleed area. After trimming, the bleed ensures that no
unprinted edges occur in the final trimmed document. It is very difficult
to print exactly to the edge of a sheet of paper/card, so to achieve this,
it is necessary to print a slightly larger area than is needed and then
trim the paper/card down to the required finished size. Images, background
images and fills which are intended to extend to the edge of the page must
be extended beyond the trim line to give a bleed. Bleeds in the US
generally are 1/8 of an inch from where the cut is to be made. Bleeds in
Europe generally are 2 to 5mm from where the cut is to be made. This can
vary from one print company to another. Some printers ask for specific
sizes; most of these companies place the specific demands on their website
or offer templates that are already set to their required bleed settings.
Line
Printer prints one entire line of text before advancing to another
line. Most early line printers were impact printers. Line printers are
mostly associated with unit record equipment and the early days of digital
computing, but the technology is still in use. Print speeds of 600
lines-per-minute (approximately 10 pages per minute) were achieved in the
1950s, later increasing to as much as 1200 lpm. Line printers print a
complete line at a time and have speeds in the range of 150 to 2500 lines
per minute. The different types of line printers are drum printers,
band-printers and chain printers. Other non-impact technologies have also
been used, as thermal line printers were popular in the 1970s and 1980s,
and some inkjet and laser printers produce output a line or a page at a
time. Many impact printers, such as the daisywheel printer and dot matrix
printer, used a print head that printed a character then moved on until an
entire line was printed. Line printers were much faster, as each impact
printed an entire line. There have been five principal designs:
Drum Printers. Chain (train) printers. Bar printers, Comb printers.
Wheel printers. Because all of these printing methods were noisy, line
printers of all designs were enclosed in sound-absorbing cases of varying
sophistication.
Several effects come together to cause this
Problem:
1. Monitors and output devices have limitations. Each device has a
range of colors it can reproduce, called its color gamut. These vary with the
type and model. The printer type, ink and paper quality and the printer's
condition also affect the results.
2. Equipment can easily become miscalibrated and require very expensive, specialized accessories to keep them
standardized to a predictable performance.
3. Printers that dither can only
create a limited number of colors. If you attempt to print a color which does
not fall within its abilities, it will produce the nearest match. The printer's
resolution is important to its dithering ability, so higher resolution printers
usually print higher quality color. Color management systems are available to
help solve these problems if precise color matching is important to you.
Matching a Color
Matching a color that is painted on a wall or on other surfaces.
Color Matching is to accurately match a color when buying new
paint, so that when you paint over the original color it blends in and you
can't tell that its been freshly painted. Color Matching can be
difficult when taking a picture, this is because there are
variations in
lighting that effects the color. You may get the color close, but it may
not be an exact match. This is why using a color measurement device is
more accurate, but you need a sample of the product or use a portable
color analyzer. So to accurately match a paint color, you need to cut a
small section or chip away a piece of the painted surface that you want to
match, and then bring that one inch square sample piece to a home center
or to a paint store to be color matched. And always know if its a matte
finish or flat finish or a
glossy
finish or somewhere in between? Most brands of paint come
in
several sheens, and both latex and oil-based paints are available in
different sheen levels. Gloss sheens have the
highest light-reflective
characteristics. Next are semigloss sheens; then satin, eggshell, or low-lustre
sheens; and then flat or matte sheens. So not only do you need to pick the
right color that is either a water based color or an oil based color, you
also need to know if the paint needs to be formulated for the interior or
the exterior, you’ll also have to choose a paint finish that is either a
glossy finish or a flatt finish or somewhere in between. Glossier satin
sheen translates to a
slicker surface or
less sticky surface that's slightly quicker and
easier to wipe clean of dust, dirt, mildew, and mold. Gloss can be
classified as follows: Full gloss: 70–90% returned light, Semi-gloss:
41–69% returned light, Satin: 26–40% returned light, Sheen: 15–25%
returned light, Eggshell: 10–15%
returned light,
Matte: <10% returned light.
Spectrophotometer is a
color measurement device used to capture and
evaluate color. As part of a color control program. A
reflectance spectrophotometer
shines a beam of light and
measures
the amount of light reflected from different wavelengths of the
visible spectrum, while a transmission spectrophotometer measures how
much light passes through the sample. Spectrophotometers can measure and
provide quantitative analysis for just about anything,
including liquids, plastics, paper, metal, fabric, and painted samples to
verify color remains consistent from conception to delivery.
multi-angle spectrophotometer views the color of a sample as if it is
being moved back and forth, just as you would twist a sample to see the
color at various angles. Today’s multi-angle instruments are used for
specially coated pigments and special effect colors with additives such as
mica and pearlescent, such as nail polish and automotive coatings. These
are typically used in the lab, on the production line, in QC operations
and in the shipping area.
Spectrophotometry is a branch of electromagnetic spectroscopy
concerned with the quantitative measurement of the reflection or
transmission properties of a material as a function of wavelength.
Spectrophotometry uses photometers, known as spectrophotometers, that can
measure the intensity of a light beam at different wavelengths. Although
spectrophotometry is most commonly applied to ultraviolet, visible, and
infrared radiation, modern spectrophotometers can interrogate wide swaths
of the electromagnetic spectrum, including x-ray, ultraviolet, visible,
infrared, and/or microwave wavelengths.
Portable
Color Analyzer for exact color matching. (amazon)
Colorimeter Color Meter Pro Color Analyzer for iOS, Android and
Windows Devices. (amazon)
Color Muse 2 Colorimeter - Color and Sheen Matching Tool - Instantly
identify the closest matching paint colors, sheen levels, and digital
color values. (amazon)
MetaVu Paint Benchtop Spectrophotometer for retail paint measurement.
Colorimeter is a device used in colorimetry that measures the
absorbance of particular wavelengths of light by a specific solution. It
is commonly used to determine the concentration of a known solute in a
given solution by the application of the Beer–Lambert law, which states
that the concentration of a solute is proportional to the absorbance.
Color Analysis
describes a method of determining the colors of clothing and makeup that
harmonizes with a person's skin complexion, eye color, and hair color for
use in wardrobe planning and style consulting. It is generally agreed that
the wrong colors will draw attention to such flaws as wrinkles or uneven
skin tone while harmonious colors will enhance the natural beauty of the
individual making them appear healthy and fresh-faced. Color analysis
(American English; colour analysis in Commonwealth English), also known as
personal color analysis (PCA), seasonal color analysis, or skin-tone
matching.
Color
Chart is a flat, physical object that has many different color samples
present. They can be available as a single-page chart, or in the form of
swatchbooks or color-matching fans. Typically there are two different
types of color charts:
Color reference charts
are intended for color comparisons and measurements. Typical tasks for
such charts are checking the color reproduction of an imaging system,
aiding in color management or visually determining the hue of color.
Examples are the IT8 and Color.
Checker Charts.
Color selection charts present a palette of available colors to aid the
selection of spot colors, process colors, paints, pens, crayons, and so on
– usually the colors are from a manufacturers product range. Examples are
the Pantone and RAL systems.