On the expression method of color

Ha ha, brother, let me talk about this problem and outline it. In the development of human material life and spiritual life, color always exudes magical charm. People not only discover, observe, create and appreciate the colorful world of color, but also deepen their understanding and application of color through the ever-changing times. People's understanding and application of color is a process from perceptual sublimation to rationality. The so-called rational color is to regularly reveal the complex color impressions directly felt from nature with the help of people's unique abstract thinking abilities such as judgment, reasoning and deduction, thus forming color theories and laws and applying them to color practice. [Edit this paragraph] The principles of light and color, three primary colors and mixed colors have been paid attention to by pioneers at home and abroad more than a thousand years ago, but since Newton, a scientist in the17th century, color has become an independent subject. Color is a comprehensive phenomenon involving light, objects and vision, and "the origin of color" naturally becomes the first proposition.

The so-called color term is the special term of color. Understanding the meaning of these nouns is not only a part of basic knowledge, but also a necessary intermediary language to explain the principles and laws of color, so it should be the content of explanation from the beginning.

First, light and color vision (vision)

Experience has proved that people's understanding and application of color is realized by finding differences and looking for their internal relations. Therefore, the most basic visual experience of human beings has reached the simplest and most important conclusion: there is no color without light. People can see colorful objects in the daytime, but they can't see anything in the dark night. If there is a light, you can see the object and its color again where the light shines.

It was the British scientist Newton who really solved the mystery of light and color. /kloc-in the second half of the 0/7th century, in order to improve the definition of the newly invented telescope, Newton began to study the phenomenon of light passing through the glass mirror. 1666, Newton conducted a famous dispersion experiment. He shut a room in the dark, and only opened a narrow gap in the window to let the sunlight in and pass through the glass prism of a triangular suspension. As a result, there was an unexpected miracle: instead of a white light, there was a seven-color light band on the opposite wall. These seven colors are arranged in the order of red, orange, yellow, green, cyan, blue and purple, much like rainbows after rain. At the same time, if the seven-color beam passes through the prism again, it can be restored to white light. This seven-color band is the solar spectrum.

A large number of scientific research results after Newton further tell us that color is an objective existence with color light as the main body and gives people a visual feeling. This feeling is based on three factors: first, light; The second is the reflection of light by objects; The third is the human visual organ-eyes. That is to say, visible light with different wavelengths is projected on the object, and some wavelengths of light are absorbed, and some wavelengths of light are reflected, which stimulates people's eyes and is transmitted to the brain through the optic nerve, forming color information about the object, that is, people's color perception.

The relationship between light, eyes and objects constitutes the basic content of color research and chromatics, and is also the theoretical basis and basis of color practice.

1. Existence conditions of colored light, visible light and spectral color

In order to understand the reason of light dispersion discovered by Newton, we must look for the answer from the essence of light.

The so-called light in the spectrum, as far as its physical properties are concerned, is an electromagnetic wave, and part of it can be accepted and reacted by human visual organs-eyes, usually called visible light. Therefore, color should be a visual phenomenon caused by visible light, which can cause visual reaction after stimulating the eyes, making people feel the color and perceive the spatial environment. Visible light is so common that anyone with normal vision can feel it. Visible light is mysterious and ever-changing, because there is no other way to contact, stabilize and understand it except to see. Therefore, many scientists, artists and thinkers at home and abroad have observed, studied and thought about this, but almost no convincing answer has been found. Although Newton decomposed light, some people described it as "breaking light".

Obviously, visible light is not solid, liquid, gas, cells, molecules, atoms, or heat, electricity or chemical energy.

With the development of science, the study of light gradually comes into contact with the essence. Newton was also the first to put forward in 1672 that light is a kind of particle emitted by an object, which is called light particle. It is emitted from a luminous body in all directions at great speed, so that the human eye can feel the light. This is the so-called particle theory.

1678, hagens and others thought that the universe was full of a thin and elastic medium called ether. When a substance emits light, its electrons vibrate and are transmitted to the distance in turn through the surrounding ether, becoming a shear wave. Shear waves enter the human eye and cause light sensation, which is called wave theory.

1864, Maxwell thought that light was not the movement of the ether itself, but the propagation caused by electromagnetic changes in the ether. Ether wave is a kind of electric wave, which is called electromagnetic theory.

Modern science has confirmed that light is a kind of radiant energy in the form of electromagnetic waves. It is both fluctuating and granular. These two properties of light are called "duality" in optics.

When sunlight passes through the prism, it propagates along different routes with different wavelengths: violet light has the shortest wavelength, the slowest propagation speed, the largest tortuosity (the largest refraction angle), red light has the longest wavelength and the smallest refraction angle, and other colors of light are arranged in turn to form a seven-color spectrum. When light strikes the surface of an opaque object, particles "collide", some of which are reflected and some are absorbed. This reflected light acts on the visual organs, forming the concept of object color. The above is a scientific answer to the dispersion phenomenon of light and the color essence of objects.

In the whole electromagnetic wave range, not all light has color. Electromagnetic waves include cosmic rays, X-rays, ultraviolet rays, infrared rays, radio waves and visible light, all of which have different wavelengths and vibration frequencies. Only electromagnetic waves with a wavelength of 380 nm to 780 nm can cause people's color perception. This wavelength is called visible spectrum, which is often called light.

Electromagnetic waves of other wavelengths are invisible to human eyes, commonly known as invisible light, but they are actually different rays or waves. Electromagnetic waves with a wavelength greater than 80 nm are called infrared rays, and electromagnetic waves with a wavelength less than 380 nm are called ultraviolet rays. All kinds of light have different wavelengths, and their size is still measured in nanometers.

If the color light decomposed by the prism is measured by a photometer, the wavelength of the color light can be obtained. Therefore, the concept of color is actually the visual reflection produced by different wavelengths of light stimulating people's eyes.

The physical properties of light are determined by the amplitude and wavelength of light waves. The difference in wavelength determines the difference in hue. The same wavelength but different amplitudes determine the difference of hue brightness, that is, brightness difference.

Only when there is light can there be color, and light comes from a light source. There are two kinds of light sources: natural light sources and artificial light sources. Now we know that sunlight, which is considered as white (or colorless), and all the light are made up of colored light with various wavelengths and frequencies in turn, which is called "spectrum". The light emitted by incandescent lamps, fluorescent lamps and other lamps with different spectra has different color feelings.

At first, the spectrum of sunlight was considered to be composed of seven colors: red, orange, yellow, green, cyan, blue and purple. Later, it was suggested that it was composed of six colors: red, orange, yellow, green, blue and purple, because the exact wavelength difference between cyan and blue light has not been determined. The viewpoint of 7-color spectrum and 6-color spectrum seems to be inconclusive in chromatics for many reasons (but now most colorists, scientists, artists and scholars agree with the viewpoint of 6-color, and most color professional books adopt the viewpoint of 6-color, mainly because the color table and color ring discharged by 6-color are convenient to explain the color principle). Because the names of spectral colors are not only concerned by scientists and artists, but also by linguists and writers, it is inevitable that there are differences in understanding the meaning of names from their own perspectives. For example, orange is actually the middle color between red and yellow, and some are called orange. In reality, the color of orange fruit is very different, that is, the color of orange itself is also divided into shades, so orange is only a general concept of all orange colors, and it is difficult to take a specific fruit as the standard. Visible color itself is not rigorous. Another example is cyan. Some people think that it comes from kyanite, so it should be blue-green, and blue is a positive color, so blue should be removed from the spectral color. In Japan, the blue of the sky is actually what we think of as sky blue, so it is customary to remove the blue and keep the blue in the Japanese spectrum. In addition, there is a view that the spectrum is only composed of four colors: red, yellow, green, blue and purple. In a word, there is no conclusion about seven colors, six colors and five colors, and it is difficult to confirm one statement and deny the other two. When reading different color theory books, there are often different opinions for the reasons mentioned above.

The six colors that meet the standard hue of color light are made of pigments, which are the standard colors of pigments, namely red, orange, yellow, green, blue and purple.

solar spectrum

range

Spectrum 2. Color of light source, color of object and inherent color

The appearance of object color is related to the color of light source and the physical characteristics of the object.

The same object will show different colors under different light sources: white paper under white light, red paper under red light and green paper under green light. Therefore, the change of the spectral components of the light source color will inevitably affect the color of the object. The object under electric lamp is yellow, the object under fluorescent lamp is blue, the object under electric welding light is light blue, the scene at dawn and sunset is orange red and yellow, the scene under sunlight is light yellow, and the scene under moonlight is light green. The light intensity of the color of the light source will also have an impact on the irradiated object. The color of objects under strong light will fade, and the natural color of objects under weak light will become blurred and dim. Only the color of an object under moderate light intensity is most clearly visible.

Physicists find that light will be absorbed, reflected and transmitted when it hits an object. And all kinds of objects have the characteristics of selective absorption, reflection and transmission of colored light. As far as the effects of objects on light are concerned, they can be roughly divided into two categories: opaque and transparent, which are usually called transparent body and transparent body. For opaque objects, their colors depend on the reflection and absorption of various colored lights with different wavelengths. If an object can reflect almost all colors of sunlight, it is white. On the other hand, if an object can absorb almost all the colored light in sunlight, then the object is black. If an object only reflects light with a wavelength of about 700 nanometers and absorbs light with other wavelengths, then the object looks red. It can be seen that the color of an opaque object is determined by its reflected colored light, which essentially refers to the characteristics of the object reflecting and absorbing some colored light. The color of a transparent object is determined by the color light it transmits. Red glass is red because it only transmits red light and absorbs light of other colors. The color filter used on the camera lens does not mean to filter out the light of the lens color, but actually lets the light of this color pass through and filters out the light of other colors. Because each object has a special function of selectively absorbing, reflecting and transmitting light of various wavelengths, it has a relatively constant color difference under the same conditions (such as light source, distance, environment and other factors). People are used to calling the color effect of an object under white light the "inherent color" of the object. For example, red flowers and green leaves under white light will never appear under red light. Safflower can appear redder, but green light does not have the characteristic of reflecting red light. On the contrary, it absorbs red light, so the green leaves appear black under red light. At this time, black, which feels like black leaves, can still be regarded as the object color of green leaves under red light, while green leaves are green because they are green under normal light source (sunlight), and green is generally regarded as the inherent color of green leaves. Strictly speaking, the so-called intrinsic color should be the color produced by "the inherent physical properties of objects" under the constant light source.

The function of light and the characteristics of an object are two indispensable conditions for the color of an object. They are interdependent and mutually restrictive. Only emphasize the characteristics of the object and deny the role of the color of the light source, and the color of the object becomes the source of waterless; Only the function of light source color is emphasized, but the inherent characteristics of the object are not recognized, which denies the existence of object color. At the same time, when using the word "inherent color", we should pay special attention not to misunderstand that the color of the object is fixed. This prejudice is the "inherent color concept" that must be overcome when studying the relationship between light and color and doing color sketch.

Second, three primary colors and mixed colors.

1. Three primary colors of pigments and colors

Brewster, a contemporary British scientist of Newton, found that four pigments, orange, green, blue and purple, can be mixed with three pigments, and more pigments can be mixed. Brewster pointed out that red, yellow and cyan are the three primary colors of pigments, that is, pigments that cannot be mixed with other pigments.

/kloc-At the beginning of the 9th century, British physiologist Yang He established his own three-base natural light theory while studying the physiological theory of human color vision. Later, the German physicist Helmholtz developed this theory, which is called Young's theory, or "triple theory", and has been constantly confirmed and improved by new scientific research results. [Edit this paragraph] Color system and application I. Classification and attributes of colors

1. Color classification

In the ever-changing color world, people feel rich colors visually, which can be divided into primary colors, intermediate colors and composite colors, but as far as color system is concerned, it can be divided into two categories: achromatic color system and colored color system.

1, type

1. Primary colors: The basic colors that cannot be decomposed are called primary colors. Primary colors can be synthesized into other colors, and other colors cannot be restored to their original colors. There are only three primary colors, the three primary colors of color light are red, green and blue, and the three primary colors of pigment are magenta (bright rose red), yellow and blue (lake blue). The three primary colors of color light can synthesize all colors and stack them together to get white light. Theoretically, the three primary colors of pigment can be mixed into any other color, and black can be added to the same tone. Because the commonly used pigments contain other chemical components besides pigments, the purity of two or more pigments will be affected when they are mixed. The more colors mixed, the lower the purity and brightness. The addition of tricolor pigments can only get a black turbid color, not pure black.

2. Intermediate color: an intermediate color made by mixing two primary colors. There are only three intermediate colors: magenta, yellow and cyan (lake blue), which are called "complementary colors" in some color photography books, referring to the complementary relationship on the color circle. The three primary colors of pigments, namely orange, green and purple, are also called secondary colors. It must be pointed out that the three colors of color and light are precisely the three primary colors of pigments. This interlaced relationship constitutes a complex relationship between color light, pigment and color vision, and also constitutes a rich content of color principles and laws.

3. Multicolor: Two primary colors or the primary colors of a pigment are mixed with their corresponding primary colors (red and green, yellow and purple, blue and orange) to obtain a multicolor, also known as the third color. Composite color contains all the primary color components, but the proportion of each primary color is not equal, thus forming different tones such as red gray, yellow gray and green gray (not listed here).

Because the three primary colors of colored light plus white light, there are two results: one is that colored light does not have complicated colors, and the other is that colored light does not have gray color matching. If the tones between the two colors are added, only a light primary color light will be produced. Take yellow light plus green light as an example:

Yellow light+cyan light = red light+green light+green light+blue light = green light+white light = bright green light

2. Color system

1. color system: refers to all colors contained in the visible spectrum, with red, orange, yellow, green, blue and purple as the basic colors. Different mixing amounts between primary colors, and different mixing amounts between primary colors and achromatic colors, all colors produced in Qian Qian belong to chromaticity system. The color system is determined by the wavelength and amplitude of light, the wavelength determines the tone, and the amplitude determines the tone.

Any color in the chromaticity system has three attributes, namely hue, lightness and purity. In other words, as long as a color has the above three attributes, it belongs to the chromatic system.

2. Non-color series: refers to various shades of gray series, consisting of black, white and black and white. Physically, they are not included in the visible spectrum, so they cannot be called colors. But as far as visual physiology and psychology are concerned, they have complete colorfulness and should be included in the color system.

Multicolor color system gradually changes from white to light gray, medium gray, dark gray and even black according to certain changing rules, which is called black and white series in chromatics. The change of black-and-white series from white to black can be represented by a vertical axis, with one end being white, one end being black, and various transitional grays in the middle. Pure white is an ideal completely reflecting object, and pure black is an ideal completely absorbing object. However, there are no pure white and pure black objects in real life. Zinc white and lead white used for pigments can only be close to pure white, and coal black can only be close to pure black.

The color of achromatic color system is only the change of lightness, but it does not have the nature of hue and purity, that is, their hue and purity are equal to zero theoretically. The brightness of two colors can be expressed in black and white, and the closer to white, the higher the brightness; The closer to black, the lower the brightness.

2. Three attributes of color

colour

Hue is the appearance and name of each color, such as red, orange, green, lake blue, ultramarine and so on. Hue is the main basis for distinguishing colors, and it is also the biggest feature of colors. There are many types and methods of naming hue, namely color and pigment.

Brightness of color circle, brightness axis and purity map

Brightness is the difference between the light and shade of a color, that is, the difference between the shades. The difference of color lightness includes two aspects: first, it refers to the change of the depth of a certain tone, such as pink, scarlet and scarlet, which are all red, but one is darker than the other. The second is the brightness difference between different colors. For example, among the six standard colors, yellow is the lightest, purple is the deepest, and the brightness of orange is similar to that of green, red and blue.

purely

Purity refers to the amount of a single standard color component contained in each color. Pure color has a strong sense of color, that is, strong chromaticity, so purity is also a sign of strong sense of color. The fineness and smoothness of the surface structure of the object is helpful to improve the purity of the color of the object. Ink with the same purity is printed on different white papers, the purity of light paper is higher, while the purity of rough paper is lower. The objects with the highest color purity are silk, wool, nylon plastic and so on.

The purity achieved by different tones is different, among which the purity of red is the highest, the purity of green is relatively low, and other tones are in the middle, and the lightness is also different. [Edit this paragraph] Basic types of color contrast I. Tone contrast

After more than two kinds of color matching, the color contrast effect caused by hue difference is called hue contrast. It is a basic aspect of color contrast, and its contrast intensity depends on the distance (angle) between hues on the color ring. The smaller the distance (angle), the weaker the contrast and the stronger the contrast.

1 .0 degree contrast

(1) Although the contrast between achromatic color and achromatic color is colorless, their combination is very valuable in practice. Such as black and white, black gray, medium gray, light gray, or black and white gray, dark black gray, light gray. The contrast effect feels generous, solemn, elegant and modern, but it is also easy to feel too simple and monotonous.

(2) achromatic colors contrast with black and red, gray and purple, or black and white and yellow, white and gray and blue. The contrast effect feels generous and lively. When the area of achromatic color is large, it tends to be elegant and solemn; when the area of color is large, the sense of liveliness is strengthened.

(3) The contrast of a tone with different lightness or purity in the same tone is commonly known as the same color combination. Such as blue and light blue (blue+white), green and pink green (green+white) and dark green (green+black). The contrast effect is uniform, quiet, elegant, implicit and steady, but it is also prone to the disadvantages of monotony and rigidity.

(4) Compared with similar colors such as white and dark blue and light blue, black and orange and brown, achromatic colors combine the advantages of types (2) and (3). On a certain level, I feel generous, lively and steady.

Harmony and contrast

(1) The adjacent two to three colors on the adjacent hue contrast color ring have a hue distance of about 30 degrees, which belongs to the weak contrast type. For example, the contrast between red, orange, yellow and orange. The effect feels soft, harmonious, elegant and quiet, but it also feels monotonous, fuzzy, boring and powerless. It is necessary to adjust the brightness difference to enhance the effect.

(2) Similar hue contrast hue contrast distance is about 60 degrees, which belongs to weak contrast type, such as red and yellow-orange contrast. The effect is rich and lively, but it does not lose the feeling of unity, elegance and harmony.

(3) The hue contrast distance of medium hue contrast is about 90 degrees, which belongs to the medium contrast type, such as yellow-green contrast. The effect is bright, lively, full, exciting and interesting. The contrast is quite strong, but there is no loss of harmony.

3. Strong contrast

(1) contrast hue The contrast hue distance is about 120 degrees, which belongs to strong contrast type, such as yellow-green, red-purple contrast. The effect is strong, eye-catching, powerful, lively and rich, but it is not easy to be unified and messy, stimulating and causing visual fatigue. Generally, various reconciliation methods are needed to improve the contrast effect.

(2) The contrast distance of complementary color contrast hue is 180 degrees, which belongs to extreme contrast types, such as red and turquoise, yellow and blue-purple. The effect is strong, dazzling, loud and powerful, but if it is not handled properly, it is easy to produce childish, primitive, vulgar, unstable and uncoordinated feelings.

Second, the contrast between cold and warm.

Cold and warm contrast is a kind of color contrast that compares the color tendency of colors. Cold and warm itself is the conditional induction of human skin to external temperature, and the cold and warm feeling of color mainly comes from people's physiological and psychological feelings. [Edit this paragraph] Stereo scale ostwald scale

We sort out the lightness, hue and color obtained after the above mixing under white light, and choose from bottom to top. The color scale on each cross section is the same, and the color scale on the upper cross section is higher than that on the lower cross section. Then black, white and gray are taken as the central axis, and the center is outside, so that the purity of color codes on the same cylinder is the same, and the purity on the outer cylinder is higher than that on the inner cylinder. Outside the central axis of the team, the hue of each vertical section is the same, so that the hues of red, orange, yellow, green, cyan, blue and purple on different vertical sections are arranged clockwise from the central axis of the ring, thus organizing thousands of color codes neatly into three-dimensional color codes. At present, the three-dimensional color scale with great influence is ostwald color scale and Mencel color scale.

Munsell color stereo is a kind of color expression created by American educator, colorist and artist Munsell. Its expression is based on three elements of color. Hue is called hue, abbreviated as H, lightness is called lightness, abbreviated as V, purity is called chroma, abbreviated as C, and the hue ring is based on five primary colors of red R, yellow Y, green G, blue B and purple P in psychology, plus their intermediate hues. Orange YR, yellow-green GY, blue-green BG, blue-purple PB and red-purple RP are called ten shades, and the arrangement order is clockwise. Then each tone is divided into ten equal parts in detail, with No.5 in the middle of each tone as the representative of each tone, and the total number of tones is one hundred.

Ostwald color stereo was created by German scientist, great colorist and Nobel Prize winner ostwald. The three-dimensional color phase ring of ostwald color is based on the four physiological primary colors of Helinder, namely yellow, blue, red and green, and the four colors are respectively placed on four equal points of the circumference to form two groups of complementary color pairs. Then four colors of orange, blue-green, purple and yellow-green are added in the middle of the two colors in turn, making a total of eight tones, and then each tone is divided into three tones, thus forming a color ring with 24 tones. Take two opposite colors on the color ring and turn gray on the turntable, then these two opposite colors are complementary colors. [Edit this paragraph] Color design and application 1. The Unity of Practicality and Aesthetics —— The Dual Role of Color in Design

Decoration and beautification of (1) color

Color plays an important role in people's social life, productive labor and daily life such as food, clothing, housing and transportation. Modern scientific research data show that more than 90% of the information received by a normal person from the outside world is input into the brain through visual organs. All visual images from the outside world, such as the boundaries and differences of the shape, space and position of objects, are reflected through the differences of colors and the relationship between light and shade, and the first impression of vision is often the feeling of colors. Interest in color leads to people's aesthetic awareness of color, which becomes a prerequisite for people to beautify their lives through color decoration. As Marx said, "the feeling of color is the most common form of general aesthetic feeling."

Color design and printing

Color is closely related to printing, but unfortunately designers often forget printing. Designers and printers are a couple. Come on, it's common for them to spark. The designer considered various factors and chose several colors, but it happened that the expected effect could not be achieved when printing. The printer secretly complained that the designer had rich imagination, regardless of whether the design was feasible or not. Mr. Cai Qiren has a deep understanding of this. He thinks that designers must know more about printing. Many designers, especially newcomers, don't know the printing process, so there will be some avoidable mistakes when copying.

Usually the most problematic thing is the printing color of printed matter, and the effect is not as good as the designer's mind. There are many reasons for this error, one of which is probably related to printing materials and printing methods. The same ink, printed with different materials and different thicknesses of paper, will definitely get different color effects; Even if the same material is printed by different printing methods, the thickness of ink will be different. For example, offset printing is thinner than flexography, which affects the brightness of color. An experienced designer will consider the characteristics of the substrate, the use of ink and the printing method in advance, and try to match the objective conditions when designing; On the other hand, designers should also communicate with printers to get to know each other and try to reduce the degree of mistakes.

Mr. Cai Qiren thinks that the appeal of color is quite great. There are no good-looking colors and bad-looking colors in the world, only designers use them. Designers, based on their own years of experience, should use brand-new ideas to express the characteristics of color, bring fresh feelings to others in design and combination, and guide the audience to further explore the meaning behind color. On the other hand, design mostly serves the promotion of goods, so designers should consider what resources customers can use, how much customers are prepared to invest in this design and so on. Of course, the most important thing is whether this color can increase the attractiveness of goods. The invisible hand of nature shows us a colorful world, and the ever-changing color collocation is fascinating; Similarly, a successful color design has vitality and can infect the emotions of the audience. Designers can have a deeper understanding and research on the use of color, and will certainly design more wonderful works.