Introduction:
Our environment is a world of colour, both natural and manually manipulated. The Oxford Dictionary describes colour as
• “The property possessed by an object of producing different
sensations on the eye as a result of the way it reflects or emits
light” and
• “One, or any mixture, of the constituents into which light can
be separated in a spectrum or rainbow, sometimes including
(loosely) black and white.”
Others define it as
• “General term that refers to the wavelength composition of
light, with particular reference to its visual appearance.” [1]
Or
• “A phenomenon of light or visual perception that enables one to differentiate otherwise identical objects” [2].
Visual Design:
Visual Design is not about what a piece is saying literally through words, but it is everything about what a piece is saying visually and emotionally- solely through appearance.
Colour Description and Colour Theories:
To understand color you must understand how these four properties relate to each other.
•
Hue: The name of the color
•
Value: The lightness or darkness of hue
•
Saturation or intensity (chroma): The purity of hue, brightness or dullness
•
Temperature: The warmth and coolness of hue.
The Science of Colour:
Touching, tasting, smelling, hearing,
and seeing—these are the ways we get our information about the world.
But the world of humans is primarily a world of sights, with 90 percent
of what we know of the world coming to us through our vision. What we see is colour. Colour is a visual experience, a sensation of
light that cannot be verified by other senses-not by touch, taste,
smell, or hearing. The eye’s retina absorbs the light sent to us from
luminous objects (eg. light bulb) or reflected from a non-luminous
object (eg. a table and chair) and sends a signal, or sensation, to the
brain. This sensation makes us aware of a characteristic of light,
which is colour.
Scientifically,
light (made up from photons) is just one form of visible energy while
colour is simply light of different wavelengths and frequencies. The
way in which most of us actually see colour, is through the sensors in
the retina of our eyes called rods and cones. The rods are very
sensitive to light but are mostly colour blind. The colour detectors in
the eye are the cones. Each cone contains one of three pigments
sensitive to RED, GREEN or BLUE. Each pigment absorbs a particular
wavelength of colour eg. short wavelength cones absorb blue light,
middle wavelength cones absorb green light, and long wavelength cones
absorb red light.
When we observe a colour that has a wavelength between that of
the primary colours red, green and blue, combinations of the cones are
stimulated. The result is that we can detect light of all colours in the
visible spectrum. Each colour has its own properties with its own
wavelength and frequency. The human eye is able to sense wavelengths of
light ranging from about 400 nm to about 700 nm. Red is the longest
visible wavelength (720 nm), followed in order by orange, yellow,
green, blue, indigo, and violet, the shortest visible wavelength (380
nm). ROYGBIV is an acronym for these wavelengths, which are the colours
of the visible spectrum. In order for an object to be seen as a
colour, the wavelengths that its colorant reflects must be present in
the light source. If a red object is placed under a source that lacks
the red wavelength, all light reaching the object is absorbed. No colour
is reflected back to the eye. A red object is seen as black under
green light.
Roses appear to be red because they contain a red pigment which absorbs
most of the visible light spectrum, while reflecting mainly red back to
the viewer.
Source (dancer): by Sanjana Reddy http://www.vogue.in
The position of the light source will
determine the angle in which the light will reach the object while the
direction of the reflected light beam will influence how colours are
perceived in terms of its lightness and darkness.
Display of density models at Venice Architectural Biennale 2006:
Photo: Shruti Hemani
Transparent, Translucent, Opaque Wine Glasses:
Source: Google
The Science of Colour Theories:
It is the light that generates colours. Without it there is no
colour. The sun, a fundamental source of light, is sensed as white (or
colourless) but it is made up of mixture of colours which can be seen by
passing the sunlight through a prism. There are two theories that
explain how colours work and interact. The light or additive theory
deals with radiated and filtered light. The pigment or subtractive
theory deals with how white light is absorbed and reflected off of
coloured surfaces.
• Light Theory:
Light theory starts with black (the absence of light). When all
of the frequencies of visible light are radiated together the result is
white (sun) light. The colour interaction is diagrammed using a colour
wheel with red, green and blue as primary colours (Red, Green and
Blue). These are the three colours that the cones in the eye sense.
This is an RGB colour system. The primary colours mix to make secondary
colours: red and green make yellow, red and blue make magenta and
green and blue make cyan. All three together add up to make white
light. That is why the theory is called additive.
A computer monitor or a
coloured television is an example of light theory. The same three
primary colours are used and mixed by the eye to produce the range of
colours you see on the screen. This theory is also used for dramatic
lighting effects on stage in a theater.
• Pigment Theory:
Pigments behave almost the opposite of light. With pigments a
black surface absorbs most of the light, making it look black. A white
surface reflects most of the (white) light making it look white. A
coloured pigment, red for instance, absorbs most of the frequencies of
light that are not red, reflecting only the red light frequency.
Because all colours other than the pigment colours are absorbed, this
is also called the subtractive colour theory. If most of the red light
is reflected the red will be bright. If only a little is reflected
along with some of the other colours the red will be dull. A light
colour results from lots of white light and only a little colour
reflected. A dark colour is the result of very little light and colour
reflected.
The primary colours in the
pigment theory have varied throughout the centuries but now cyan,
magenta and yellow are increasingly being used. These are the primary
colours of ink, along with black, that are used in the printing
industry. This is a CMYK colour system [Cyan, Magenta, Yellow and (K)
black].
Light Effects:
• Opaque, Translucent and Transparent:
If all the light reaching the object is transmitted, the object
is transparent eg. Clear glass. When the light reaching the object is
partly reflected and partly absorbed, the object is translucent eg.
Butter paper or tracing paper. If all the light reaching an object is
either reflected or absorbed, the object is opaque eg. Ceramic teapot.
• Luminosity:
Luminosity is the attribute of emitting light without heat. A
luminious object is light reflective but does not emit heat.
• Indirect Light/Colour:
An indirect colour is the variant of indirect light. An
indirect colour occurs when a light reaches a highly reflective colour
on a broad surface and reflects onto the nearby object which changes
its apparent colour due to the reflect light /colour.
Scattering:
The position of the light source will determine the angle in
which the light will reach the object while the direction of the
reflected light beam will influence how colours are perceived in terms
of its lightness and darkness. Different textured surface does not
affect the actual colour (wavelength) of the light but a smooth surface
will reflect more light directly than a matt or rough surface which
reflects light in a more fragmented way. Hence the smooth surface may
appear lighter and brighter than a rough surface. Heavily textured or
irregular surfaces scatter light is many directions and can created
light-dark variations of colours that make it dynamic and lively.
Varying textures of surface allows designers to create such effects when
their scope is limited to only one colour or material. Emboss
materials or frosted glassware create patterns with single colour or
material.
