Colors absorbing light: Which Colors Reflect More Light?

Color

Light absorption

When a molecule interacts with light and energy is absorbed, the molecule is said be excited and a transition occurs which can take the molecule from an initial state to a higher energy state

Within the one-electron approximation, this is described by the promotion of an electron from a filled orbital to an unfilled orbital (in the case of diamagnetic materials). The difference in energy between those levels, (the excited state and the ground state), gives the energy of the photons that can be absorbed.

Several parameters can be used to characterize this transition, including the energy of the incident radiation required for the efficient absorption of the light and the inherent ability of the molecules to absorb radiation of the appropriate energy by the Planck relation:

where hv is the energy of the photon corresponding to the energy gap between the states. The energy is reported in several units; the following is helpful for translating between some common units one comes across in the literature:

1 eV = 23.06 kcal/mol = 8065 cm^-1 = 1240 nm

Color

Our perception of color is determined by what wavelengths of radiation reach our eye and the sensitivity of the receptors in our eye to various colors The eye has rods and cones containing chromophores which convert light into electrical impulse that the brain uses to perceive images. This the opposite of what you see in light emitting diodes in which electricity causes emission of light.

The rods function under low intensity conditions and provide images in shades of black, grey, and white This is referred to as scotopic vision

The cones process images of high intensity in color which is referred to as photopic vision. Cones come in three varieties which correspond roughly to blue, green, and red sensitivities; if all three cones are simultaneously excited, then the image will appear white.

Complementary Colors

This graphic shows what color will be perceived when a material absorbs in certain regions of the visible spectrum.

If wavelengths of light from a certain region of the spectrum are absorbed by a material, then the materials will appear to be the complementary color Thus, for instance, if violet light with wavelength of 400nm is absorbed, the material will look yellow. If the material absorbs blue you will see the color orange.

Note that green is not indicated in the figure; this is because materials that appear green actually absorb in the red and the blue (i. e., about 650 nm and 425 nm) band shape and color

Our ability to perceive very small differences in color is rather extraordinary; for instance, two solutions which appear to have virtually identical absorption spectra, with minute differences in their tails, can be recognized as clearly different hues. Very small changes in the shape of an absorption band (not only the position) will cause materials to appear different shades

Bright and Dull

A sharp absorption peak results in the perception of a saturated color.

In general, colors that we perceive as brilliant and bright have strong narrow absorption bands whereas dull colors tend to have weaker and broader absorption bands.

Color Description

The hue is that aspect of color usually associated with terms such as red, orange, yellow, and so forth.Hue distinguishes the color purity of the dominant color (i. e. red from yellow). The position of absorption maxima largely determines this property.

saturation (also known as chroma, or tone) refers to relative purity; when a pure, vivid, strong shade of red is mixed with a variable amount of white, weaker or paler reds are produced, each having the same hue but a different saturation; such paler colors are called unsaturated colors. You can define the amount of saturation of a given using a chromaticity diagram. For example, suppose you had a red color and you slowly increased the amount of blue and green light reaching the eye, then the mixture of the red, blue and green would contribute to the perception of white. White plus red would give pink. The hue would not have been altered, but the saturation would be lower

Light of any given combination of hue and saturation can have a variable brightness (also called intensity, lightness, or value), which depends on the total amount of light energy present. Lightness of a color is changed by varying the intensity of all three primary colors by the same amount. For example, if the intensity of a red were increased it would appear brown.

All colors can be create by the addition of the primary colors. Use this Flash application to explore color mixing.

Which Colors Reflect More Light?

••• Idzanake/iStock/GettyImages

Updated April 23, 2018

By Chris Deziel

When light strikes a surface, some of its energy is reflected and some is absorbed. The color a person perceives indicates the wavelength of light being reflected. White light contains all the wavelengths of the visible spectrum, so when the color white is being reflected, that means all wavelengths are being reflected and none of them absorbed, making white the most reflective color.

TL;DR (Too Long; Didn’t Read)

As a form of energy called electromagnetic radiation, light travels in waves with some of its colors having longer wavelengths than others. The visible light humans see as the color white consists of a rainbow of colors in the electromagnetic spectrum that range from blue to red, with yellow, orange, green and multiple variations sandwiched between them, as in a rainbow after a storm. Blue and violet have shorter wavelengths and higher energy, and, at the opposite end of the spectrum, red wavelengths are longer, but have lower energy.

From Total to Zero Reflectivity

If the color of a surface is anything other than white, it means that it absorbs light of some wavelengths. For example, a surface that appears red absorbs yellow, green, blue and violet light, while reflecting red light. A surface that appears green absorbs all colors except green. White light is a combination of all colors — as is apparent when you shine a white light through a prism — so anything that appears white reflects all wavelengths of light. Black is the least reflective color, it’s the color of a surface that absorbs all light.

Tints and Shades

If a surface isn’t white, then the closer its color is to white, the more light it reflects. Pastel and off-white colors reflect more light than deep tones. Adding white to a color is called tinting the color, and it increases the color’s reflectivity. The contrasting procedure is to add black to decrease the reflectivity. This is called shading.

Different Colors in Different Lights

An object that is white, would look red in a red-colored light because white contains all colors. But if a blue light were shined on a red ball, the color on the ball would be very dark, because the red color only contains red, not blue, so it absorbs the blue light instead of reflecting it. The color of an object depends on the light cast upon it. The only way to know the color of an object is to put it into sunlight or white light.

Heat Absorption

Darker colored objects heat up faster in the sun than light colored ones, which is why running across asphalt in bare feet can feel much hotter than walking across light-colored concrete. The reason is that darker colors absorb more of the different wavelengths of light energy, while white or light-colored objects reflect the light of most wavelengths.

Related Articles

References

• University of California at Santa Barbara: Which Colors Absorb the Most Heat?
• University of Kentucky: The Physics of Light

About the Author

Chris Deziel holds a Bachelor’s degree in physics and a Master’s degree in Humanities, He has taught science, math and English at the university level, both in his native Canada and in Japan. He began writing online in 2010, offering information in scientific, cultural and practical topics. His writing covers science, math and home improvement and design, as well as religion and the oriental healing arts.

Light and color: the basics of the basics / Sudo Null IT News

We often talk about such a concept as light, light sources, color of images and objects, but we don’t quite understand what light is and what color is. It is time to deal with these issues and move from representation to understanding.

We are surrounded

Whether we realize it or not, we are in constant interaction with the outside world and take on the influence of various factors of this world. We see the space around us, we constantly hear sounds from various sources, we feel heat and cold, we do not notice that we are under the influence of natural background radiation, and we are constantly in the radiation zone that comes from a huge number of sources of telemetry, radio and telecommunication signals. Almost everything around us emits electromagnetic radiation. Electromagnetic radiation is electromagnetic waves created by various radiating objects – charged particles, atoms, molecules. Waves are characterized by repetition frequency, length, intensity, and a number of other characteristics. Here is just an introductory example. The heat emanating from a burning fire is an electromagnetic wave, or rather infrared radiation, and of very high intensity, we do not see it, but we can feel it. The doctors took an x-ray – irradiated with electromagnetic waves with a high penetrating power, but we did not feel and did not see these waves. The fact that electric current and all devices that operate under its influence are sources of electromagnetic radiation, of course, you all know. But in this article I will not tell you the theory of electromagnetic radiation and its physical nature, I will try to explain in a less simple language what visible light is and how the color of the objects that we see is formed. I started talking about electromagnetic waves to tell you the most important thing: Light is an electromagnetic wave that is emitted by a heated or excited state of matter. The role of such a substance can be played by the sun, an incandescent lamp, an LED flashlight, a fire flame, various kinds of chemical reactions. There can be quite a lot of examples, you yourself can bring them in much more than I wrote. It should be clarified that by the term light we mean visible light. All of the above can be represented in the form of such a picture (Figure 1). nine0005

Figure 1 – The place of visible radiation among other types of electromagnetic radiation.

In Figure 1 , visible light is shown as a scale that consists of a “mixture” of different colors. As you may have guessed, this is spectrum . A wavy line (sinusoidal curve) passes through the entire spectrum (from left to right) – this is an electromagnetic wave that reflects the essence of light as electromagnetic radiation. Roughly speaking, any radiation is a wave. X-ray, ionizing, radio emission (radio receivers, television communications) – it does not matter, they are all electromagnetic waves, only each type of radiation has a different wavelength of these waves. A sinusoidal curve is just a graphical representation of radiated energy that changes over time. This is a mathematical description of the radiated energy. In figure 1, you can also notice that the depicted wave seems to be slightly compressed in the left corner and expanded in the right. This suggests that it has a different length in different areas. The wavelength is the distance between its two adjacent peaks. Visible radiation (visible light) has a wavelength that varies from 380 to 780nm (nanometers). Visible light is just a link in one very long electromagnetic wave. nine0005

From light to color and back

You know from school that if you put a glass prism in the path of sunlight, most of the light will pass through the glass and you will be able to see the colored bands on the other side of the prism. That is, initially there was sunlight – a beam of white color, and after passing through a prism it was divided into 7 new colors. This suggests that white light is made up of these seven colors. Remember, I just said that visible light (visible radiation) is an electromagnetic wave, and so, those multi-colored stripes that turned out after the passage of the sun’s ray through a prism are separate electromagnetic waves. That is, 7 new electromagnetic waves are obtained. Look at Figure 2.

Figure 2 – The passage of a beam of sunlight through a prism.

Each wave has its own length. You see, the peaks of neighboring waves do not coincide with each other: because the red color (red wave) has a length of about 625-740nm, the orange color (orange wave) has a length of about 590-625nm, the blue color (blue wave) has a length of 435-500nm., I will not give figures for the remaining 4 waves, I think you understand the essence. Each wave is an emitted light energy, i.e. a red wave emits red light, an orange wave emits orange, a green wave emits green, and so on. When all seven waves are emitted at the same time, we see a spectrum of colors. If we mathematically add the graphs of these waves together, then we get the original graph of the electromagnetic wave of visible light – we get white light. Thus, we can say that the spectrum of an electromagnetic wave of visible light is the sum of waves of different lengths, which, when superimposed on each other, give the original electromagnetic wave. The spectrum “shows what the wave consists of.” Well, to put it quite simply, the spectrum of visible light is a mixture of colors that make up white light (color). I must say that other types of electromagnetic radiation (ionizing, X-ray, infrared, ultraviolet, etc.) also have their own spectra.

Any radiation can be represented as a spectrum, although there will be no such colored lines in its composition, because a person is not able to see other types of radiation. Visible radiation is the only type of radiation that a person can see, which is why this radiation is called visible. However, the energy of a certain wavelength does not have any color by itself. Human perception of electromagnetic radiation in the visible range of the spectrum occurs due to the fact that in the human retina there are receptors that can respond to this radiation. nine0005

But can we get white only by adding the seven primary colors? Not at all. As a result of scientific research and practical experiments, it has been found that all the colors that the human eye can perceive can be obtained by mixing just three primary colors. Three primary colors: red, green, blue. If by mixing these three colors you can get almost any color, then you can get white! Look at the spectrum that was shown in Figure 2, three colors are clearly visible on the spectrum: red, green and blue. It is these colors that underlie the RGB (Red Green Blue) color model. nine0005

Let’s see how it works in practice. Let’s take 3 light sources (spotlights) – red, green and blue. Each of these spotlights emits only one electromagnetic wave of a certain length. Red – corresponds to the radiation of an electromagnetic wave with a length of approximately 625-740nm (the beam spectrum consists only of red), blue emits a wave of 435-500nm (the beam spectrum consists of blue only), green – 500-565nm (only green color in the beam spectrum ). Three different waves and nothing else, there is no multi-colored spectrum and additional colors. Now let’s direct the spotlights so that their beams partially overlap each other, as shown in Figure 3.

Figure 3 – The result of superimposing red, green and blue colors.

Look, where the light rays cross each other, new light rays have formed – new colors. Green and red formed yellow, green and blue – cyan, blue and red – magenta. Thus, by changing the brightness of the light rays and combining colors, you can get a wide variety of color tones and shades of color. Pay attention to the center of the intersection of green, red and blue: in the center you will see white. The one we talked about recently. nine0015 White color is the sum of all colors. It is the “strongest color” of all the colors we see. The opposite of white is black. Black color is a complete absence of light at all. That is, where there is no light, there is darkness, everything becomes black there. An example of this is illustration 4.

Figure 4 – No light emission

I somehow imperceptibly move from the concept of light to the concept of color and I don’t tell you anything. It’s time to be clear. We found out that light is the radiation that is emitted by a heated body or a substance in an excited state. The main parameters of the light source are the wavelength and light intensity. Color is a qualitative characteristic of this radiation, which is determined on the basis of the resulting visual sensation. Of course, the perception of color depends on the person, his physical and psychological condition. But let’s assume that you are feeling well enough, reading this article and you can distinguish the 7 colors of the rainbow from each other. I note that at the moment, we are talking about the color of light radiation, and not about the color of objects. Figure 5 shows color and light parameters that are dependent on each other. nine0005

Figures 5 and 6 – Dependence of color parameters on the source of radiation

There are basic color characteristics: hue, brightness (Brightness), lightness (Lightness), saturation (Saturation).

Hue

– This is the main characteristic of a color that determines its position in the spectrum. Remember our 7 colors of the rainbow – in other words, 7 color tones. Red color tone, orange color tone, green color tone, blue, etc. There can be quite a lot of color tones, I gave 7 colors of the rainbow just as an example. It should be noted that such colors as gray, white, black, as well as shades of these colors do not belong to the concept of color tone, as they are the result of mixing different color tones. nine0005

Brightness

– A characteristic that shows how strongly the light energy of a particular color tone (red, yellow, violet, etc.) is emitted . What if it doesn’t radiate at all? If it is not radiated, then it is not there, but there is no energy – there is no light, and where there is no light, there is black color. Any color at the maximum decrease in brightness becomes black. For example, a chain of reducing the brightness of red: red – scarlet – burgundy – brown – black. The maximum increase in brightness, for example, the same red color will give “maximum red color”. nine0005

Lightness

– The degree to which a color (hue) is close to white. Any color at the maximum increase in lightness becomes white. For example: red – crimson – pink – pale pink – white.

Saturation

– The degree to which a color is closer to gray. Gray is an intermediate color between white and black. The gray color is formed by mixing in equal to amounts of red, green, blue with a decrease in the brightness of radiation sources by 50%. Saturation changes disproportionately, i.e. lowering the saturation to a minimum does not mean that the brightness of the source will be reduced to 50%. If the color is already darker than gray, it will become even darker as the saturation is lowered, and as the saturation decreases further, it will turn completely black.

Color characteristics such as hue (hue), brightness (Brightness), and saturation (Saturation) form the basis of the HSB color model (otherwise called HCV). nine0005

In order to understand these color characteristics, let’s look at the color palette of the Adobe Photoshop graphics editor in Figure 7.

Figure 7 – Adobe Photoshop Color Palette

If you look closely at the picture, you will find a small circle, which is located in the upper right corner of the palette. This circle shows which color is selected on the color palette, in our case it is red. Let’s start to figure it out. First, let’s look at the numbers and letters that are located on the right half of the picture. These are the parameters of the HSB color model. The topmost letter is H (hue, color tone). It determines the position of a color in the spectrum. A value of 0 degrees means that it is the highest (or lowest) point on the color wheel – that is, it is red. The circle is divided into 360 degrees, i.e. It turns out that it has 360 color tones. The next letter is S (saturation, saturation). We have a value of 100% – this means that the color will be “pressed” to the right edge of the color palette and have the maximum possible saturation. Then comes the letter B (brightness, brightness) – it shows how high the point is on the color palette and characterizes the intensity of the color. A value of 100% indicates that the color intensity is at its maximum and the dot is “pressed” to the top edge of the palette. The letters R(red), G(green), B(blue) are the three color channels (red, green, blue) of the RGB model. In each, each of them indicates a number that indicates the amount of color in the channel. Recall the spotlight example in Figure 3, when we figured out that any color can be made by mixing three light beams. By writing numerical data to each of the channels, we uniquely determine the color. In our case, the 8-bit channel and the numbers range from 0 to 255. The numbers in the R, G, B channels indicate the light intensity (color brightness). We have a value of 255 in the R channel, which means that this is a pure red color and it has the maximum brightness. Channels G and B are zeros, which means the complete absence of green and blue colors. In the lowest column you can see the code combination #ff0000 – this is the color code. Each color in the palette has its own hexadecimal code that defines the color. There is a wonderful article Color theory in numbers, in which the author tells how to determine the color by a hexadecimal code. nine0119
In the figure, you can also notice the crossed-out fields of numerical values ​​​​with the letters “lab” and “CMYK”. These are 2 color spaces, according to which colors can also be characterized, they are generally a separate conversation and at this stage there is no need to delve into them until you understand RGB.
You can open the Adobe Photoshop Color Palette and play around with the color values ​​in the RGB and HSB fields. You will notice that changing the numeric values ​​in the R, G, and B channels will change the numeric values ​​in the H, S, B channels.

The color of objects

It’s time to talk about how it happens that the objects around us take on their color, and why it changes with different lighting of these objects.

An object can only be seen if it reflects or transmits light. If the object almost completely absorbs the incident light, then the object takes on black color . And when the object reflects almost all the incident light, it takes on the white color . Thus, we can immediately conclude that the color of the object will be determined by the number absorbed and reflected light with which this object is illuminated. The ability to reflect and absorb light is determined by the molecular structure of the substance, in other words, by the physical properties of the object. The color of the object “is not inherent in it by nature”! By nature, it contains physical properties: to reflect and absorb.

The color of the object and the color of the radiation source are inextricably linked, and this relationship is described by three conditions.

— First condition: An object can acquire color only if there is a light source. If there is no light, there will be no color! Red paint in a can will look black. In a dark room, we cannot see or distinguish colors because there are none. There will be a black color of the entire surrounding space and objects in it. nine0005

– Second condition: The color of the object depends on the color of the light source. If the light source is a red LED, then all objects illuminated by this light will have only red, black and gray colors.

– And finally, the Third condition: The color of an object depends on the molecular structure of the substance of which the object is composed.

Green grass looks green to us because, when illuminated with white light, it absorbs the red and blue wavelengths of the spectrum and reflects the green wavelength (Figure 8). nine0005

Figure 8 – Reflection of the green wave of the spectrum

The bananas in Figure 9 look yellow because they reflect the waves lying in the yellow region of the spectrum (yellow spectrum wave) and absorb all other waves of the spectrum.

Figure 9 – Reflection of the yellow wave of the spectrum

The dog, the one shown in Figure 10, is white. White color is the result of reflection of all waves of the spectrum.

Figure 10 – Reflection of all waves of the spectrum

The color of the object is the color of the reflected spectrum wave. This is how objects acquire the color we see.

In the next article we will talk about a new color characteristic – color temperature.

reflection and absorption of light – Blog – Ghenadie Sontu Fine Art

November 29, 2020

Light and color are the result of electromagnetic disturbances of some body, moving in space in waves. Light waves have different lengths. The wavelength is very short and is measured in millimicrons or nanometers (nm): 1 mm = 1 × 10–3 micron (micron) = 1 × 10–6 mm. A millimicron is equal to one millionth of a millimeter. Vibrations with a wavelength ranging from 400 to 750 millimicrons are perceived by the optic nerves and cause a sensation of light of various colors. Waves longer than 750 millimicrons are infrared rays, and waves shorter than 400 millimicrons are ultraviolet rays, both of which the human eye is not able to catch. nine0005

Daylight consists of a wide variety of wavelengths. If you install a white screen in a dark room and pass a sunbeam through a small hole on it, then a bright spot of white color will appear on the screen. If, however, a glass prism is placed in the path of the sun’s ray, then a stripe painted in the colors of the rainbow will appear on the screen. It is called the solar spectrum, which is the result of the decomposition of sunlight into its component parts. Therefore, sunlight is a mixture of a number of rays with different wavelengths, which together create the impression of white. nine0005

A beam of light passes through a prism and is split into a spectrum

The light wave of each color has its own length and frequency of oscillation. Light waves themselves have no color. Color comes from the perception of our eyes and brain.

The color of the surrounding material objects is formed from the absorption and reflection of light waves. White light hits an object, some of the light waves are absorbed, some are reflected. If all the waves are absorbed, then we will see black. If all the waves are reflected, we will see white light. If waves of a certain length and frequency are reflected, then we will see the color corresponding to this light wave:

All colors of the spectrum except orange are absorbed. Orange is reflected and we see orange

The origin of color from light rays form two basic natures of color:

Additive colors – colors formed by outgoing light rays. Traffic lights, television, computers, telephones work on the basis of additive color rendering – wherever colored light rays and effects based on them are used. nine0005

Subtractive colors are colors formed by the reflection of light from material objects. In fact, this is everything material and material that surrounds us, both created by nature and created by man. This nature of color has another name – pigment color, and substances that affect and change color are called pigments.

In addition to the method of formation of color, the two color natures have significant differences – these are the primary colors and the method of formation of additional colors. Let’s take a closer look at how this happens. nine0005

The solar spectrum visible to the eye consists of seven primary colors: red, orange, yellow, green, blue, indigo and violet. Invisible infrared, which has wavelengths longer than red, is behind it, and invisible ultraviolet, which has wavelengths shorter than violet, is behind violet. Each primary color of the spectrum gradually passes through numerous shades into the adjacent one.

The spectrum known to us contains primary and secondary colors. And here comes the essential difference between additive and subtractive colors:

Basic additive colors – green, blue, red. If you combine additive colors, then a white color is formed, in the absence of color rays a black color is formed. Complementary colors are formed by combining the rays of the three primary. The example shows that when red and green additive colors are combined, yellow is formed, when red and blue are combined – purple, when the primary three colors are combined – white. :

nine0008 An example of the RGB color model. The combination of green and red forms yellow. Three primary colors: green, blue, red – form white.

Basic subtractive colors – yellow, blue, red. If you mix the primary subtractive colors, then black is formed. Complementary colors are formed by mixing pigments of primary colors. For example, when red and yellow subtractive colors are combined, orange is formed, when red and blue are combined – purple, when the main three colors are combined – black:

The combination of three primary colors: blue, red, yellow form black. The combination of yellow and blue is green.

In the left half of the spectrum – from red to half green – are the so-called warm colors , and in the right half – from the middle of green to purple – cold colors. The warmth of colors increases from the middle of the spectrum towards red, their coldness towards violet. Green approaching yellow has a warm tint, and approaching blue a cold tint. The division of colors into warm and cold is based on the fact that red, orange and yellow can depict sunlight, fire, etc., blue, blue, purple – shadows, twilight, ice, water, etc.

Chromatic colors are all colors of the spectrum and the color shades derived from them. In the example, the colors are arranged according to the way they are formed. The triangle inside is formed by the primary colors: red, yellow, blue. Further, three triangles of additional colors included in the spectrum formed by a combination of primary colors adjoin the triangle of primary colors: green – from blue and yellow, orange – from red and yellow, violet – from red and blue. The outer ring is formed from a combination of primary colors, secondary colors and intermediate colors formed from their mixing. nine0005

Achromatic colors – Colors that do not have a hue and differ from each other only in lightness (white, gray, black) are called achromatic; all other colors differ not only in lightness, but also in chromaticity, they are called chromatic.

Color has three basic properties: lightness (luminosity), hue (color) and saturation (intensity, purity, brightness).

The lightness of the color is determined by the amount of reflected light. Achromatic colors – white, gray, black – have different lightness. The same applies to chromatic colors: if you compare them with each other, you will see that some of them are lighter, others are darker.

When a paint is mixed with white or black, it becomes a lighter or darker color of the same hue.

nine0008 A strongly lightened violet color closer to lilac and has little resemblance to spectral violet.

If you mix paint with gray equal to it in lightness, you can get tones from purer to blacker, depending on the amount of gray entered. The degree of difference between a chromatic color and an achromatic color equal to it in lightness is called saturation.

We feel all the variety of colors because different bodies reflect only certain light rays, which we perceive with our eyes in the form of rays of different colors. Therefore, light is a physical phenomenon, and the sensation of color that occurs when a visual color is irritated is a physiological phenomenon. nine0005

Transparent bodies do not block rays and let them pass through them, opaque bodies reflect them. Therefore, the different coloring of objects is due to the fact that they have a different ability to absorb and reflect certain rays of sunlight.

The impression of visual color occurs when an object reflects a green ray and absorbs all others. The black color is the result of the complete absorption of all rays. With partial absorption and partial reflection of rays by the body, it appears gray. If more rays are absorbed than reflected by the body, then its gray color is perceived as darker, in the reverse situation – lighter. nine0005

The sensation of white color occurs when all the rays of the spectrum are completely reflected or optically mixed. White color is also obtained as a result of reflection and mixing of not all, but only two specific rays. Two colors of the spectrum that cause the impression of white when optically mixed are called complementary colors. The complementary color to red is bluish-green, to orange is cyan, to yellow is blue, to yellow-green is violet.

Paints do not completely reflect the beam of any particular color and do not completely absorb all the others, therefore, in terms of purity and saturation of colors, they cannot be compared with the colors of the solar spectrum. Therefore, when mixing paints with paints, their additional colors of white cannot be obtained, and when mixing paints of all colors, a mixture of dirty, almost black color is formed. nine0005

When mixing colors of non-complementary colors, intermediate colors are obtained, for example, a mixture of red and yellow gives orange, yellow and green – yellow-green, blue and red – purple. In the latter case, the violet color, if the colors of the spectrum are arranged not in the form of a straight band, but in the form of a circle, will occupy a place in the spectrum between red and blue, which are in contact with each other.

The desired color can be obtained in two ways: by making mixtures of paints and by applying paints in transparent layers one on top of the other. nine0005

When applying paints in thin transparent layers on top of each other – when glazed – optical mixing of colors occurs . Its essence is as follows.

If a transparent layer of blue oil paint is applied to a white ground, and another layer of transparent yellow paint is applied on top, then the light falling on the upper transparent layer will hardly be reflected and will pass through it further, and some rays will be absorbed inside the yellow paint layer, and in contact with the underlying blue paint, the light will no longer be white, but yellow. Penetrating further through the layer of blue transparent paint, the yellow-colored light also undergoes absorption of some rays, as a result of which the light of yellow and blue, i.e. green, reaches the white opaque paint of the ground, is reflected from it and passes back through a layer of blue and then yellow paint. As a result, rays of light are mixed with and a yellowish green color is obtained. If the yellow layer were on the bottom, and the blue layer on top, then the result would be a bluish-green color, since the reflected light is always mixed with a certain amount of rays reflected from the paint layer superimposed on top. Glazing achieves great purity and transparency of colors; for example, kraplak, ultramarine, applied on a white surface with a transparent layer, bear little resemblance to these paints mixed with white. Showing one color of paint through another gives effects that often cannot be achieved by simply mixing paints. nine0005

During mechanical mixing of paints, light is partially reflected from the surface of the paint layer, partially refracted, passes into the depth of the layer, and as light penetrates into the paint mixture, the light rays are more and more absorbed by the particles of paint pigments, therefore, only very little light. Reflected from the paint layer are only those rays that are not absorbed by the mixed paints.

Therefore, when performing their creative work and solving color problems, artists use not only mixtures of colors obtained on the palette, but also resort to glazes, which give greater expressiveness, purity, depth and lightness of color tones. nine0005

The human eye perceives the strength and color composition of light not only naturally, unconsciously, as they enter it from outside. The eye has the ability to adapt to the light and color acting on it, not only as a whole, but also by separate parts of its retina. This ability of the eye explains the phenomenon of color contrasts. If you look closely at a painted surface, and then look at another painted surface with a different light intensity, this will affect the power of perception of the color of the second surface by the eye, namely: if the first surface is darker than the second, then this latter will appear lighter than she really is.