I am a programmer by training, but at work I had to deal with image processing. And then an amazing and unknown world of color spaces opened up for me. I don’t think that designers and photographers will learn anything new for themselves, but perhaps someone will find this knowledge at least useful, and at best interesting.

The main purpose of color models is to make it possible to specify colors in a unified way. In essence, color models define certain systems coordinates that allow you to unambiguously determine the color.

The most popular color models today are: RGB (mainly used in monitors and cameras), CMY(K) (used in printing), HSI (widely used in machine vision and design). There are many other models. For example, CIE XYZ (standard models), YCbCr, etc. The following is given short review these color models.

RGB color cube

From Grassmann's law arises the idea of ​​an additive (i.e., based on mixing colors from directly emitting objects) model of color reproduction. A similar model was first proposed by James Maxwell in 1861, but greatest distribution she received it much later.

In the RGB model (from the English red - red, green - green, blue - blue) all colors are obtained by mixing three basic colors (red, green and blue) in different proportions. The share of each base color in the final color can be perceived as a coordinate in the corresponding three-dimensional space, which is why this model is often called a color cube. In Fig. Figure 1 shows a model of a color cube.

Most often, the model is built so that the cube is a single cube. The points corresponding to the basic colors are located at the vertices of the cube, lying on the axes: red - (1;0;0), green - (0;1;0), blue - (0;0;1). In this case, secondary colors (obtained by mixing two basic ones) are located at other vertices of the cube: cyan - (0;1;1), magenta - (1;0;1) and yellow - (1;1;0). Black and white colors are located at the origin (0;0;0) and the point furthest from the origin (1;1;1). Rice. shows only the vertices of the cube.

Color images in the RGB model are constructed from three separate image channels. In Table. shows the decomposition of the original image into color channels.

In the RGB model, a certain number of bits are allocated for each color component, for example, if 1 byte is allocated for encoding each component, then using this model you can encode 2^(3*8)≈16 million colors. In practice, such coding is redundant, because Most people are unable to distinguish that many colors. Often limited to the so-called. “High Color” mode in which 5 bits are allocated for encoding each component. Some applications use a 16-bit mode in which 5 bits are allocated for encoding the R and B components, and 6 bits for encoding the G component. This mode, firstly, takes into account a person’s higher sensitivity to the color green, and secondly, it allows for more efficient use of the features of the computer architecture. The number of bits allocated to encode one pixel is called color depth. In Table. examples of encoding the same image with different color depths are given.

Subtractive CMY and CMYK models

The subtractive CMY model (from the English cyan - blue, magenta - magenta, yellow - yellow) is used to produce hard copies (prints) of images, and in some way is the antipode of the RGB color cube. If in the RGB model the basic colors are the colors of light sources, then the CMY model is a color absorption model.

For example, paper coated with yellow dye does not reflect blue light, i.e. we can say that the yellow dye subtracts blue from the reflected white light. Similarly, cyan dye subtracts red from reflected light, and magenta dye subtracts green. That is why this model is usually called subtractive. The algorithm for converting from an RGB model to a CMY model is very simple:

It is assumed that RGB colors are in the range. It is easy to see that to obtain black in the CMY model, you need to mix cyan, magenta and yellow in equal proportions. This method has two serious drawbacks: firstly, the black color obtained as a result of mixing will look lighter than “real” black, and secondly, this leads to significant dye costs. Therefore, in practice, the CMY model is expanded to the CMYK model, adding black to the three colors.

Color space hue, saturation, intensity (HSI)

The RGB and CMY(K) color models discussed earlier are very simple in terms of hardware implementation, but they have one significant drawback. It is very difficult for a person to operate with the colors specified in these models, because... When describing colors, a person does not use the content of the basic components in the color being described, but uses slightly different categories.

Most often people operate the following concepts: hue, saturation and lightness. At the same time, when talking about color tone, they usually mean color. Saturation shows how diluted the color being described is with white (pink, for example, is a mixture of red and white). The concept of lightness is the most difficult to describe, and with some assumptions, lightness can be understood as the intensity of light.

If we consider the projection of the RGB cube in the direction of the white-black diagonal, we get a hexagon:

All gray colors (lying on the diagonal of the cube) are projected onto the central point. To use this model to encode all the colors available in the RGB model, you need to add vertical axis lightness (or intensity) (I). The result is a hexagonal cone:

In this case, the hue (H) is set by the angle relative to the red axis, saturation (S) characterizes the purity of the color (1 means a completely pure color, and 0 corresponds to a shade of gray). It is important to understand that hue and saturation are not defined at zero intensity.

The conversion algorithm from RGB to HSI can be performed using the following formulas:

The HSI color model is very popular among designers and artists because... This system provides direct control of hue, saturation and brightness. These same properties make this model very popular in machine vision systems. In Table. shows how the image changes with increasing and decreasing intensity, hue (rotated by ±50°) and saturation.

CIE XYZ model

For the purpose of unification, an international standard was developed color model. As a result of a series of experiments, the International Commission on Illumination (CIE) determined the addition curves of the primary colors (red, green and blue). In this system, each visible color corresponds to a certain ratio of primary colors. At the same time, in order for the developed model to reflect all visible to humans colors had to enter a negative number of base colors. To get away from negative values CIE, introduced the so-called unreal or imaginary primary colors: X (imaginary red), Y (imaginary green), Z (imaginary blue).

When describing color, the X,Y,Z values ​​are called standard fundamental excitations, and the coordinates derived from them are called standard color coordinates. Standard addition curves X(λ),Y(λ),Z(λ) (see Fig.) describe the sensitivity of the average observer to standard excitations:

In addition to standard color coordinates, the concept of relative color coordinates is often used, which can be calculated using the following formulas:

It is easy to see that x+y+z=1, which means that to uniquely specify relative coordinates, any pair of values ​​is sufficient, and the corresponding color space can be represented as a two-dimensional graph:

The set of colors defined in this way is called a CIE triangle.
It is easy to see that the CIE triangle only describes hue, but does not describe brightness in any way. To describe brightness, an additional axis is introduced, passing through a point with coordinates (1/3;1/3) (the so-called white point). The result is a CIE color solid (see Fig.):

This body contains all the colors visible to the average observer. The main disadvantage of this system is that using it, we can only state the coincidence or difference of two colors, but the distance between two points of this color space does not correspond to the visual perception of the color difference.

Model CIELAB

The main goal in developing CIELAB was to eliminate the non-linearity of the CIE XYZ system from the point of view of human perception. The abbreviation LAB usually refers to the CIE L*a*b* color space, which this moment is an international standard.

In the CIE L*a*b system, the L coordinate means lightness (ranging from 0 to 100), and coordinates a,b– indicate a position between green-purple and blue-yellow. Formulas for converting coordinates from CIE XYZ to CIE L*a*b* are given below:

where (Xn,Yn,Zn) are the coordinates of the white point in CIE XYZ space, and

In Fig. sections of the CIE L*a*b* color body are presented for two lightness values:

Compared to CIE XYZ system Euclidean distance (√((L1-L2)^2+(a1^*-a2^*)^2+(b1^*-b2^*)^2)) in CIE L*a system *b* is a much better match for the color difference perceived by humans, however, the standard formula for color difference is the extremely complex CIEDE2000.

Television color difference color systems

In the YIQ and YUV color systems, color information is represented as a luminance signal (Y) and two color difference signals (IQ and UV, respectively).

The popularity of these color systems is primarily due to the advent of color television. Because The Y component essentially contains the original grayscale image; the signal in the YIQ system could be received and correctly displayed on both old black and white TVs and new color ones.

The second, perhaps more important advantage of these spaces is the separation of information about the color and brightness of the image. The fact is that the human eye is very sensitive to changes in brightness, and much less sensitive to changes in color. This allows chrominance information to be transmitted and stored at a reduced depth. It is on this feature of the human eye that today’s most popular image compression algorithms (including jpeg) are built. To convert from RGB space to YIQ, you can use the following formulas:

Color tone

What is denoted by the word “color” in the professional vocabulary of artists is defined in scientific color science by the term “color tone.”

Color tone is the quality of chromatic color, when determining which color is called red, yellow, blue, green; the characteristic of a color being different from other colors in the spectrum. In our minds, color tone is associated with the color of familiar objects. Many color names come from objects with a characteristic color: sand, emerald, chocolate, cherry, which indicates the inextricable connection of color with the objective world. The terms “lightness” and “color tone” are closely related in content to the concepts of “light” and “color”. In nature, color tone and lightness appear inseparably. And their separation is one of the conventions visual arts, depending on the artist’s creative attitude, the type of his vision, the material and technique he uses. However, an absolute distinction cannot be made theoretically between the concepts of “lightness” and “color tone”. If, for example, we take blue paint, diluted to varying degrees with white, then we have lightness gradations or changes in its lightness. The same will happen with any other paint, but if we take one of the light gradations of blue and one of the light gradations of red. Then we will have to have pink and blue paints. “Painting is the transmission of tone (i.e., aperture of color), plus color, of visible material,” said N. P. Krymov. This once again demonstrates that every colorful spot contains a color characterized by three interconnected indicators - “lightness”, “hue”, “saturation”. And when a paint changes in lightness, some paints have less, while others have a greater change in color tone.

Saturation

Saturation - color strength - the degree of difference between a chromatic color and a gray color of equal lightness; the degree of approximation to a pure spectral color or the percentage of color in a given hue. The closer a color approaches the spectral color, the stronger its difference from gray, the more saturated it is. Pink, light yellow, light blue or dark brown are low saturated colors. In practice, low-saturated colors are obtained by adding white or black paint to the chromatic color. An admixture of white makes the color lighter, and black paint makes it darker. Darkening or lightening a color always reduces its saturation. Saturation also depends on the color tone. Yellow is always more saturated than red, red is always more saturated than blue.

In color science, it is often not the saturation that is perceived visually that is measured, but the so-called purity, or colorimetric color saturation, which is determined by the ratio of the brightness of the spectral component to the overall brightness of the color. Purity of color - relative value and is usually expressed as a percentage. The purity of spectral colors is taken as one, or 100 percent, and the purity of achromatic colors is zero. Knowing hue, lightness, and color saturation, you can quantitatively measure any color. The slightest change in one of the three values ​​that determine color entails a change in color. The method of determining color using the three listed characteristics, convenient because color can be determined quantitatively, is successfully used in various fields of science and technology, including printing, textile production, color television, etc., where special instruments are used to measure color - spectrophotometers and colorimeters of various systems. All methods for determining color in colorimetry are based on comparing colors that lie in the same plane and are under the same lighting conditions. In painting, when working from life, the artist must analyze and compare the colors inherent in volumetric objects or objects that are complex in shape, which, as a rule, are surrounded by a color environment or objects of a different color and which are located on several, sometimes quite distant from each other, plans and , therefore, and different conditions lighting.

Color circle

The colors of the spectrum - red, yellow, blue - are called primary colors. They cannot be obtained by mixing other colors. If you mix the two extreme colors of the spectrum - red and violet, you get a new intermediate color - purple. As a result, we have eight colors considered the most important in practice: yellow, orange, red, purple, violet, blue, cyan and green. By closing this strip into a ring, you can get a color wheel with the same sequence of colors as in the spectrum. If you mix adjacent colors in different proportions in a color wheel of eight colors, you can get many intermediate shades. By mixing orange with yellow, we get orange-yellow and yellow-orange, etc. Color wheels can vary in the number of colors they contain, but not more than 150, because more eyes cannot distinguish.

The color wheel can be divided into two parts so that one part includes red, orange, yellow and yellow-green colors, and the other includes blue-green, cyan, indigo, and violet. The first of them are called warm colors, the second - cold. Classifying colors as warm or cold is based on the fact that red, orange and yellow colors resemble the color of fire, sunlight, and hot objects; blue, blue, purple colors reminiscent of the color of water, airy distance, ice. Clean green color considered neutral. It can be warm if yellowish tints are noticeable in it, and cold if bluish and bluish tints predominate in it.

Color brightness is a characteristic of perception. It is determined by our speed of identifying one tone against the background of others.

This is a relative characteristic and can only be known through comparison. Complex shades, mixed with gray or brown, create the necessary contrast so that our eye can highlight the tones that best fit this definition.

Bright tones are shades close to the pure spectrum. If the surface of the material reflects one or another wave (c) with the least distortion, then we consider that this tone is bright.

The admixture of white or black slightly affects the brightness of the color. So burgundy can be quite bright, like light yellow. Yellow-green is also a striking tone, as an intermediate wavelength between green and yellow.

Each spectrum has its own lightness: bright yellow is the lightest; the darkest are blue and purple.
The intermediate ones are: blue, green, pink, red.

This statement is true if we consider a line of shades of the same color.

If you single out the brightest shade among other tones, then the brightest will be the color that differs as much as possible in lightness from the rest.

Bright shades set a contrast with duller, darker or lighter shades, due to which we consider the combination to be rich and expressive.

USEFUL ARTICLES ON THIS TOPIC (click on the picture)

Color plays a huge role not only in art, but also in everyday life. Few people think how much different combinations shades affect human perception, mood and even thinking. This is a kind of phenomenon that operates according to its own seemingly illusory, but clear laws. Therefore, it is not so difficult to subjugate him to your will so that he works for good: you just have to figure out how he acts.

Concept

Color is a subjective characteristic of electromagnetic radiation in the optical range, which is determined on the basis of the resulting visual impression. The latter depends on many physiological and psychological reasons. Its understanding can be equally influenced by its spectral composition and the personality of the person perceiving it.

To put it simply, color is the impression a person receives when a beam of light rays penetrates the retina. A beam of light with the same spectral composition can cause different sensations in different people due to distinctive features sensitivity of the eye, so the shade may be perceived differently for each person.

Physics

The color vision that appears in the human mind includes semantic content. Tone is created by the absorption of light waves: for example, a blue ball appears that way only because the material from which it is made absorbs all shades of light except the blue, which it reflects. Therefore, when we talk about a blue ball, we only mean that the molecular composition of its surface is capable of absorbing all colors of the spectrum except blue. The ball itself has no tone, like any object on the planet. Color is born only in the process of lighting, in the process of perception of waves by the eye and processing of this information by the brain.

The eye and brain can achieve a clear distinction between the shade and its main characteristics through comparison. Therefore, values ​​can only be determined by comparing the color with other achromatic shades, including black, white and gray. The brain is also able to compare the hue with other chromatic tones in the spectrum by analyzing tone. Perception is a psychophysiological factor.

Psychophysiological reality is, in essence, a color effect. The shade and its effect may coincide when using harmonic halftones; in other situations, the color may vary.

It is important to know the basic characteristics of colors. This concept includes not only its actual perception, but also the influence of various factors on it.

Basic and additional

Mixing certain pairs of colors can create the impression of white. Complementary are opposite tones that, when mixed, produce gray. The RGB triad is named after the main colors of the spectrum - red, green and blue. In this case, cyan, magenta and yellow will be additional. On the color wheel, these shades are located in opposition, opposite each other, so that the meanings of two triplets of colors alternate.

Let's talk in more detail

The main physical characteristics of color include the following points:

• brightness;
• contrast (saturation).

Each characteristic can be measured quantitatively. The fundamental differences in the main characteristics of color are that brightness implies lightness or darkness. This is the content of a light or dark component, black or white, while contrast provides information about the content of gray tone: the less it is, the higher the contrast.

Also, each shade can be specified by three unique coordinates, representing the main characteristics of the color:

• lightness;
• saturation.

These three indicators are able to determine a specific shade, starting from the main tone. Basic characteristics of color and their fundamental differences described by the science of colorism, which deals with a deep study of the properties of this phenomenon and its influence on art and life.

Tone

The color characteristic is responsible for the location of the hue in the spectrum. Chromatic tone is one way or another assigned to one or another part of the spectrum. Thus, shades located in the same part of the spectrum (but differing, for example, in brightness) will belong to the same tone. When you change the position of a hue along the spectrum, it changes color characteristic. For example, when blue is shifted towards green, the tone changes to cyan. Moving in reverse side, blue will tend towards red, taking on a purple tint.

Warm-coldness

Often a change in tone is associated with the warmth and coldness of the color. Red, red and yellow shades They are classified as warm, associating them with fiery, “warming” colors. They are associated with corresponding psychophysical reactions in human perception. Blue, violet, light blue symbolize water and ice, referring to cold shades. The perception of “warmth” is associated with both physical and psychological factors of the individual personality: preferences, the mood of the observer, his psycho-emotional state, adaptation to environmental conditions, and much more. Red is considered the warmest, blue is considered the coldest.

It is also necessary to highlight the physical characteristics of the sources. Color temperature is largely associated with the subjective feeling of warmness of a particular shade. For example, the tone of a thermal study as the temperature increases passes through the “warm” tones of the spectrum from scarlet to yellow and, finally, white. However, the highest color temperature has cyan, which is nevertheless considered a cold shade.

Among the main characteristics within the hue factor is also activity. Red is said to be the most active, while green is the most passive. This characteristic can also be somewhat modified under the influence of the subjective views of different people.

Lightness

Shades of the same hue and saturation can refer to different degrees of lightness. Let's consider this characteristic in terms of blue. With the maximum value of this characteristic, it will be close to white, having a soft bluish tint, and as the value drops, blue will become more and more like black.

Any tone will turn into black when the lightness is decreased, and when increased absolutely - white.

It should be noted that this indicator, like all other basic physical characteristics of color, can largely depend on subjective conditions related to the psychology of human perception.

By the way, shades of different tones, even with similar actual lightness and saturation, are perceived differently by a person. Yellow is in fact the lightest, while blue is the darkest shade of the chromatic spectrum.

At high performance yellow is even less distinguishable from white than blue is from black. It turns out yellow tone has even greater intrinsic lightness than the “darkness” characteristic of blue.

Saturation

Saturation is the level of difference between a chromatic hue and an achromatic hue of equal lightness. In essence, saturation is a characteristic of depth and purity of color. Two shades of the same tone can have different levels of fade. As saturation decreases, every color will become closer to gray.

Harmony

Another one of general characteristics color, which describes a person’s impressions of a combination of several shades. Each person has his own preferences and tastes. Therefore, people have different ideas about the harmony and disharmony of different types of colors (with the color characteristics characteristic of them). Harmonious combinations are shades that are close in tone or from different parts of the spectrum, but with similar lightness. As a rule, harmonious combinations do not have high contrast.

As for the rationale for this phenomenon, this concept should be considered in isolation from subjective opinions and personal tastes. The impression of harmony arises under conditions of fulfillment of the law on complementary colors: the equilibrium state corresponds to a gray tone of medium lightness. It is obtained not only by mixing black and white, but also a couple of additional shades, if they contain the main colors of the spectrum in a certain proportion. All combinations that do not produce gray when mixed are considered disharmonious.

Contrasts

Contrast is the difference between two shades, revealed by comparing them. By studying the main characteristics of color and their fundamental differences, we can identify seven types of contrast manifestations:

1. Contrast of comparisons. The most pronounced ones are variegated blue, yellow and red. As you move away from these three tones, the intensity of the hue weakens.
2. Contrast of dark and light. There are maximally light and maximally dark shades of the same color, and in between there are countless manifestations.
3. Contrast of cold and warm. The poles of contrast are recognized as red and blue, and other colors can be warmer or cooler in accordance with how they relate to other cold or warm tones. This contrast can only be known through comparison.
4. Contrast of complementary colors - those shades that, when mixed, produce neutral gray. Opposite tones need each other to balance. Couples have their own types of contrasts: yellow and violet represent the contrast of light and dark, and red-orange and blue-green represent warmth and coldness.
5. Simultaneous contrast - simultaneous. This is a phenomenon in which the eyes, when perceiving a particular color, need an additional shade, and in its absence, it generates it on its own. Simultaneously generated shades are an illusion that does not exist in reality, but it creates special impressions from the perception of color combinations.
6. Saturation contrast characterizes the contrast between saturated colors and faded ones. The phenomenon is relative: the tone, even without being pure, may seem brighter next to a faded shade.
7. Color spread contrast describes the relationships between color planes. It has the ability to enhance the manifestations of all other contrasts.

Spatial impact

Color has properties that can influence the perception of depth through contrasts of dark and light, as well as changes in saturation. For example, all light colors against a dark background will visually come forward.

As for warm and cool shades, warm tones will come to the fore, and cool tones will go deeper.

Saturation contrast makes bright colors stand out against muted tones.

Spread contrast, also called color plane magnitude contrast, plays great importance in the appearance of the illusion of depth.

Color is an amazing phenomenon of this world. It is able to influence perception, deceive the eye and brain. But if you understand how this phenomenon works, you can not only maintain clarity of perception, but also make color become a faithful assistant in life and art.

1. What is color?
2. Physics of color
3. Primary colors
4. Warm and cool colors

What is color?

Color is waves of a certain kind of electromagnetic energy, which, after perception by the human eye and brain, are converted into color sensations (see physics of color).

Color is not available to all animals on Earth. Birds and primates have full color vision; others, at best, can distinguish some shades, mainly red.

The appearance of color vision is associated with the way we eat. It is believed that in primates it appeared in the process of searching for edible leaves and ripe fruits. In further evolution, color began to help a person determine danger, remember the area, distinguish between plants, and determine impending weather by the color of the clouds.

Color as a carrier of information began to play a huge role in human life.

Color as a symbol. Information about objects or phenomena colored in specific color, united into an image that made a symbol out of color. This symbol changes its meaning depending on the situation, but is always understandable (it may not be conscious, but accepted by the subconscious).
Example: red in a “heart” is a symbol of love. A red traffic light is a warning of danger.

With the help of color images you can convey more information to the reader. This linguistic understanding of color.
Example: I put on black
There is no hope in the soul,
I hate the white light.

Color causes aesthetic pleasure or displeasure.
Example: Aesthetics is expressed in art, although it consists not only of color, but also of form and subject. You, without knowing why, will say that it is beautiful, but this cannot be called art.

Color affects our nervous system, causes the heartbeat to increase or slow down, affects metabolism, etc.
For example: a room painted blue seems cooler than it actually is. Because blue slows down our heartbeat and immerses us in peace.

With each century, color carries more and more information for us, and now there is such a thing as “the color of culture,” color in political movements and societies.

Physics of color

Color as such does not exist in nature. Color is a product of mental processing of information that enters through the eye in the form of a light wave.

A person can distinguish up to 100,000 shades: waves from 400 to 700 millimicrons. Outside the distinguishable spectra lie infrared (with a wavelength greater than 700 n/m) and ultraviolet (with a wavelength less than 400 n/m).

In 1676, I. Newton conducted an experiment on splitting a light beam using a prism. As a result, he received 7 clearly distinguishable colors of the spectrum.

These colors are often reduced to 3 primary colors (see primary colors)

Waves have not only a length, but also an oscillation frequency. These quantities are interrelated, so you can set a specific wave either by the length or the frequency of oscillations.

Having obtained a continuous spectrum, Newton passed it through a collecting lens and obtained white color. Thus proving:

1 White color consists of all colors.
2 For color waves, the principle of addition applies
3 Lack of light leads to lack of color.
4 Black is the complete absence of color.

During the experiments, it was found that the objects themselves do not have color. Illuminated by light, they reflect some of the light waves and absorb some, depending on their physical properties. The reflected light waves will be the color of the object.
(For example, if we shine light on a blue mug through a red filter, we will see that the mug is black because blue waves are blocked by the red filter, and the mug can only reflect blue waves)

It turns out that the value of paint is in its physical properties, but if you decide to mix blue, yellow and red (because the rest of the colors can be obtained from a combination of primary colors (see primary colors)), you will not get white (as if you mixed waves), but an indefinite dark color, since in this case the principle of subtraction applies.

The principle of subtraction says: any mixing leads to the reflection of a wave with a shorter wavelength.
If you mix yellow and red, you get orange, which has a wavelength shorter than the wavelength of red. When red, yellow and blue are mixed, the result is an indefinitely dark color - a reflection tending to the minimum perceptible wavelength.

This property explains the soiling of white color. White color is a reflection of all color waves; the application of any substance leads to a decrease in reflection, and the color becomes not pure white.

Black is the opposite color. To stand out on it, you need to increase the wavelength and the number of reflections, and mixing leads to a decrease in the wavelength.

Primary colors

Primary colors are the colors that can be used to create all the others.

This is RED YELLOW BLUE

If you mix red, blue and yellow color waves with each other, you get white.

If you mix red, yellow and blue paints, you get a dark, indeterminate color (see physics of color).

These colors differ in lightness, in which brightness is at its peak. If you convert them to black and white format, you will clearly see the contrast.

It is difficult to imagine a bright dark yellow color as bright light red. Due to brightness in different lightness ranges, a huge range of intermediate bright colors is created.

RED+YELLOW=ORANGE
YELLOW+BLUE=GREEN
BLUE+RED=PURPLE

Hue, brightness, saturation, lightness

Tone is the main characteristic by which colors are named.

For example, red or yellow. There is an extensive color palette based on 3 colors (blue, yellow and red), which, in turn, are short for the 7 primary colors of the rainbow (because by mixing the primary colors you can get the missing 4)

Tones are obtained by mixing different proportions primary colors.

Tones and shades are synonymous.

Halftone is a slight but noticeable change in color.

Brightness is a characteristic of perception. It is determined by our speed of highlighting one color against the background of others.

Bright colors are considered to be “pure” colors, without any admixture of white or black. Each tone has its maximum brightness at a different lightness: hue/lightness.

This statement is true if we consider a line of shades of the same color.

If you single out the brightest shade among other tones, then the brightest will be the color that differs as much as possible in lightness from the rest.

Saturation (intensity) – This is the degree of expression of a certain tone. The concept operates in the division of one tone, where the degree of saturation is measured by the degree of difference from gray: saturation/lightness

This concept is also related to brightness, since the most saturated tone in its line will be the brightest.

The lightness scale shows that the higher the saturation, the lighter the tone.

Lightness is the degree to which a color differs from white and black. If the difference between the detected color and black is greater than between it and white, then the color is light. If it’s the other way around, it’s dark. If the difference between black and white is equal, then the color is average in lightness.

To more conveniently determine the lightness of a color, without being distracted by the tone, you can convert the colors to black and white:

Lightness is an important property of color. The determination of dark and light is a very ancient mechanism, it is observed in the simplest single-celled animals to distinguish between light and darkness. It was the evolution of this ability that led to color vision, but until now the eye is more readily attracted to the contrast of light and dark than to any other.

Warm and cool colors

Warm and cool colors are associated with the attributes of the seasons. Cool shades are those inherent in winter, and warm shades are those associated with summer.

This is the “undefined” that lies on the surface when you first encounter a concept. This is true, but the real principle of separation lies much deeper.

The division into cold and warm is based on wavelength. The shorter the wave, the cooler color The longer the wave, the warmer the color.

Green is a border color: shades of green can be cold and warm, but at the same time they retain a middle position in their properties.

The green spectrum is the most comfortable for the eye. Largest quantity We distinguish shades in this color.

Why exactly this division: cold and warm? After all, waves have no temperature.

At first, the division was intuitive because the effect of short-wave spectra is calming. The feeling of lethargy is reminiscent of the human condition in winter. Long-wave spectra, on the contrary, promoted activity, which is similar to the condition in summer. (see color psychology)

It’s clear with the primary colors. But there are many complex shades that are also classified as cold or warm.

The influence of lightness on color temperature.

First, let's determine: are black and white colors cold or warm?

White color is the presence of all colors at the same time, which means that it is the most balanced and neutral in temperature. In terms of its properties, green tends to match it. (we can distinguish a huge number of white shades)

Black color – absence of colors. The shorter the wave, the cooler the color. Black has reached its apogee - its wavelength is 0, but due to the absence of waves, it can also be classified as neutral.

For example, let's take the color red, which is definitely warm, and consider its light and dark shades.

The warmest color will be a “pure wave”, rich, bright red color (which is in the middle).

How do you get a darker shade of red?

Red mixes with black and takes on some of its properties. More precisely, in this case, neutral mixes with warm and cools it. The higher the degree of “dilution” of red with black, the closer the temperature of burgundy is to black.

How do you get a lighter shade of red (pink)?

White, with its neutrality, dilutes the warm red color. Due to this, red loses “amount” of heat, depending on the mixing ratio.

Colors diluted with black or white will never move from the warm to cool category: they will only approach neutral properties.

Temperature neutral colors

Colors that are cold and cool can be called neutral in temperature. warm shade in one lightness. For example: hue/lightness

Color contrasts

When two opposites are correlated, according to any quality, the properties of each of the group are multiplied. For example, a long strip appears even longer next to a short one.

Using 7 contrasts, you can emphasize one or another quality in color.

There are 7 contrasts:

1 built on the difference between colors. It is a combination of colors close to certain spectrums.

This contrast affects the subconscious. If we consider color as a source of information about the world around us, then such a combination will carry an informational message. (and in some cases cause epilepsy).

The most expressive example is the combination of white and black.

Perfect for achieving the effect of certainty.

As already mentioned in the article about lightness of color: it is easier to see the difference between light and dark than to correlate shades. Due to this contrast, you can achieve three-dimensionality and realism in the image.

Based on the difference between “inhibiting” and exciting colors. To create thermal color contrast, in pure form, the colors are taken the same lightness.

This contrast is good for creating images with different activity: from “ snow queen" to "fighter for justice."

Complementary colors are colors that, when mixed, produce grey colour. If you mix the spectra of complementary colors, you get white.

In Itten's circle, these colors are opposite each other.

This is the most balanced contrast because together the complementary colors achieve the "sweet spot" (white), but the problem is that they fail to create movement or purpose. Therefore, these combinations are rarely used in everyday life, as they create the impression of intense passions, and it is difficult to remain in this state for a long time.

But in painting this tool is very appropriate.

– it does not exist outside of our perception. This contrast, more than others, confirms the desire of our consciousness for the golden mean.

Simultaneous contrast is the creation of the illusion of an additional color on an adjacent shade.

This is most evident in the combination of black or gray with aromatic (different from black and white) colors.

If you look intently at each gray rectangle in turn, waiting for the eye to get tired, then the gray will change its shade to a complementary one in relation to the background.

On orange, gray will take on a bluish tint,

On red - greenish,

Violet has a yellowish tint.

This contrast is more harmful than beneficial. To extinguish it, you should add a shade of the main color to the changing color. More precisely, if you add yellowness to the gray color and set it against an orange background, then the simultaneous contrast will be reduced to zero.

You can familiarize yourself with the concept of saturation .

I will add that unsaturated colors can also include darkened, lightened, complex, not bright colors.

Pure contrast in saturation is based on the difference between bright and not bright colors in one lightness.

This contrast gives a feeling of moving forward bright colors against a background that is not bright. Using contrast in saturation, you can emphasize a wardrobe detail and place accents.

Based on the quantitative difference between colors. In this contrast, balance or dynamics can be achieved.

It has been noted that to achieve harmony there should be less light than dark.

The lighter the spot on a dark background, the less space it takes up for balance.

For colors of equal lightness, the space occupied by the spots is equal.

Psychology of color, color meaning

Color combinations

Color harmony

The harmony of colors lies in their consistency and strict combination. When selecting harmonious combinations, it is easier to use watercolor paints, and having certain skills in selecting tones on paints, it will not be difficult to cope with threads.

The harmony of colors obeys certain laws, and in order to better understand them, it is necessary to study the formation of colors. To do this, use a color wheel, which is a closed spectrum band.

At the ends of the diameters, dividing the circle into 4 equal parts, there are 4 main pure colors - red, yellow, green, blue. When we talk about “pure color,” we mean that it does not contain shades of other colors adjacent to it in the spectrum (for example, red, in which neither yellow nor blue shades are noticeable).

Next, on the circle, between the pure colors, intermediate or transitional colors are placed, which are obtained by mixing adjacent pure colors in pairs in different proportions (for example, by mixing green with yellow, several shades of green are obtained). Each spectrum can have 2 or 4 intermediate colors.

By mixing each color separately with white and black paint, you get light and dark colors one color, such as blue, light blue, dark blue, etc. Bright hues disposed with inside color wheel, and dark ones - from the outer one. Having filled in the color wheel, you will notice that in one half of the circle there are warm colors (red, yellow, orange), and in the other half there are cool colors (blue, cyan, violet).

Green can be warm if it contains an admixture of yellow, or cold - with an admixture of blue. Red color can also be warm - with a yellowish tint and cold - with a blue tint. A harmonious combination of colors lies in the balance of warm and cold tones, as well as consistency various colors and shades among themselves. Most in a simple way Determining harmonious color combinations is finding these colors on the color wheel.

There are 4 groups of color combinations.

Monochrome- colors that have the same name, but different lightness, that is, transitional tones of the same color from dark to light (obtained by adding black or white paint to one color different quantities). These colors are most harmoniously combined with each other and are easy to select.

The harmony of several tones of the same color (preferably 3-4) looks more interesting and richer than a single-color composition, for example white, light blue, blue and dark blue or brown, light brown, beige, white.

Monochrome combinations are often used in embroidery of clothes (for example, on a blue background they are embroidered with dark blue, light blue and white threads), decorative napkins (for example, on a plain linen they are embroidered with brown, light brown, beige threads), as well as in artistic embroidery of leaves and flower petals to convey light and shade.

Related colors are located in one quarter of the color wheel and have one common main color (for example, yellow, yellow-red, yellowish-red). There are 4 groups of related colors: yellow-red, red-blue, blue-green and green-yellow.

Transitional shades of the same color are well coordinated with each other and combine harmoniously, since they contain a common main color. Harmonious combinations of related colors are calm and soft, especially if the colors are weakly saturated and close in lightness (red, purple, violet).

Related-contrasting colors are located in two adjacent quarters of the color wheel at the ends of the chords (that is, lines parallel to the diameters) and contain one common color and two other color components, for example, yellow with a red tint (yolk) and blue with a red tint (violet). These colors are coordinated (united) with each other by a common (red) shade and are harmoniously combined. There are 4 groups of related-contrasting colors: yellow-red and yellow-green; blue-red and blue-green; red-yellow and red-blue; green-yellow and green-blue.

Related-contrasting colors are harmoniously combined if they are balanced by an equal amount of the common color present in them (that is, red and green colors are equally yellowish or bluish). These color combinations look sharper than related ones.

Contrasting colors. Diametrically opposite colors and shades on the color wheel are the most contrasting and inconsistent with each other.

The more colors differ from each other in hue, lightness and saturation, the less they are in harmony with each other. When these colors come into contact, a variegation that is unpleasant to the eye appears. But there is a way to coordinate contrasting colors. To do this, intermediate colors are added to the main contrasting colors, which harmoniously connect them.