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Channels in Photoshop. Color, light and RGB. Photoshop Image Modes

Understanding what you see in each channel gives you the knowledge to create complex highlights and fine-tune your images. In this article, you'll take a look inside the different color channels, starting with the most common image mode: RGB.

Let me make a reservation right away that the article does not cover. They are so important that they will be described in a separate article.

RGB channels

If you are preparing an image that will be sent to an inkjet printer, probably one you have at home (rather than a print shop), the mode RGB- what you need. After all, your monitor is RGB, just like your digital camera and scanner. Photoshop does not display individual channels in red, green and blue - they are shown in grayscale so you can easily see the areas that are most saturated with color. Because colors in this mode are made of light, white indicates areas where the color is at its fullest, black indicates areas where it is faint, and shades of gray represent everything in between.

As you can see in the picture above, each channel contains different information:

Red. It is typically the lightest of the bunch and shows the most color variation. In the example given, it is very light, because there is a lot of red on the girl’s skin and hair. It can be very important when editing skin tone.

Green. You can think of it as the "contrast center" because it usually has the most contrast (this makes sense since digital cameras have twice as many green sensors as red or blue sensors). Keep this in mind when creating a layer mask to sharpen an image or when working with displacement maps.

Blue. Typically the darkest of the group, it can be useful when you need to create a complex selection to isolate an object. This is where you will encounter problems such as noise and grain.

CMYK channels

While you probably spend most of your time working with RGB images, you may also need to work with images in CMYK. Its name refers to cyan, magenta, yellow and black inks used by commercial printers to print newspapers, magazines, product packaging and so on. This mode also has a composite channel.

If you plan to print the image on a regular laser or inkjet printer, you won't need one. Plus, this mode robs you of several precious filters and adjustment layers. Professional letterpress printing, on the other hand, divides the CMYK of your image into individual color separations. Each division is a perfect copy of the color channel you see in Photoshop, printed in the appropriate color (cyan, magenta, yellow or black). When a printing press layers these four colors on top of each other, they form a full-color image (this technique is known as four-color printing).

Because they represent colors rather than light, grayscale information has the opposite meaning than RGB. In this mode, black indicates full strength and white indicates the weakest expression of the color.

Spot channels

In the CMYK printing environment, there is a special type of finished ink called spot color, which requires a special kind of channel. If you're a graphic designer working in pre-press, product design, or an advertising agency, you'll need to know how to work with spot colors.

Channels Lab

Lab mode Separates brightness values ​​(how bright or dark an image is) from color information. This color mode is not used for image output like the RGB and CMYK modes, but instead is useful when you want to change only the brightness values ​​of an image (while sharpening or brightening it), without shifting the colors.

In a similar way, you can adjust just the color information (say, to get rid of a hue) without changing the brightness value. And if you look at the palette, you will see images that look like x-rays.

The following channels are available in Lab mode:

  • Brightness. It contains desaturated parts of the image, it looks like a really nice black and white version. Some people swear that by separating it into a new document and then doing a little editing, you can create a black and white image worthy of Ansel Adams.
  • A. It contains half of the color information: a mixture of magenta (understand as "red") and green.
  • b. the other half: a mixture of yellow and blue.

Multichannel mode

You will not need this mode unless you are preparing images for printing in a printing house. However, you may end up in this mode by accident. If you delete one of the document's color channels in RGB, CMYK, or Lab mode, Photoshop will switch the document to that mode without warning. If this happens, use the History palette to go back a step or press Ctrl+Z to undo your action.

There is no composite channel in this mode. This mode is designed exclusively for two- or three-color print jobs, so when you switch to it, the program will convert any existing color channels to spot ones.

When you convert an image to this mode, Photoshop immediately performs one of the following operations (depending on where you were previously):

  • Converts RGB to cyan, magenta and yellow spot channels;
  • converts CMYK to cyan, magenta, yellow and black spot;
  • converts Lab into alpha channels named Alpha 1, Alpha 2 and Alpha 3;
  • Converts Grayscale to spot black.

These changes cause drastic color shifts, but you can edit them individually, both the content and the spot color, to create the image you want.

Once you're done editing, save the image as a PSD or as a DCS 2.0 file if you need to transfer it to your prepress software.

Single channel modes

The other picture modes are not very interesting since they only have one channel. These modes include Bitmap, Grayscale, Duotone, and Indexed Color.

If you notice an error in the text, select it and press Ctrl + Enter. Thank you!

I recently read a translation of an article using channels in Photoshop on a “famous” site. The article emphasized that Photoshop does not distinguish between colors and sees all images in black and white gradations. Photoshop shows color images because we “expect” to see them in color, and it quietly adds some numbers that make the magic happen. It is not clear what the logic of such reflections is based on. Either because old versions of Photoshop showed the channels as black and white prints, or because of something else. It’s not surprising that questions in the comments in the style of “wow, so it turns out that from a black and white photo you can make a color one?”

For that matter, Photoshop doesn’t see anything at all. Photoshop is simply a program written by a person in a programming language. Photoshop does not see gray, white, red or green. Photoshop navigates graphics like Neo in the Matrix. He sees pixels as a collection of zeros and ones, and makes decisions based on digital parameters. Photoshop does nothing more than change digital values, the values ​​are converted into colors that the human eye can recognize. Other animals' eyes are structured differently, and they apparently need some other Photoshop, but it hasn't worked out yet.

It is also unclear where, finally, our domestic accessible and understandable articles about Photoshop, color, printing are, where our Dan Margulies are. The entire RuNet translates Western designers and graphics teachers. It seems that we have had design itself and good designers for a long time, and the only famous writer on the RuNet so far is Artemy Lebedev, and even then, he writes about something of his own. In this article I will try to address the issue of channels, going through the basics of the appearance of light and color along the way. We will go through the entire logic of the appearance of colors on the screen from beginning to end, and I assure you that by the end you will understand the essence of channels in Photoshop no worse than Dan Margulis. I'll start with the basics and tell you how color comes about in the first place. What is the difference between light and color. This is very important for a correct understanding of the channels. Moreover, I will try to cover not only RGB channels, but also channels in CMYK and LAB.

Photoshop color space and channels

Let's agree right away: channels and color space are not the same thing. If we're talking about channels, then we're talking about channels. And not about RGB channels or CMYK channels. What is color space in Photoshop? Color space is the essence, the formula by which Photoshop assembles an image. The channels directly depend on the color space in which Photoshop works. If the color space is RGB, then these are 3 RGB channels, if the color space is CMYK, then these are other channels, channels for the CMYK color space. But there are many color spaces, and each has its own channels! It turns out the topic is bottomless? Margulis only scribbles ABC books one after another in the Lab space, but we just have an article. It's not that scary. Once you understand how the channels of one color space are arranged, you can easily understand the others. Therefore, we will start with RGB channels, but first let’s get started with the theory.

Color space in Photoshop switches to Image > Mode. If you go to this menu, you will see a series of color spaces in which Photoshop can work. This Bitmap, Grayscale, Duotone, Indexed Color, RGB, CMYK, Lab and Multichannel. Accordingly, each of these modes has its own channels, arranged in its own way. The channels themselves for any image can be viewed in the channels panel Windows > Channel. By opening this panel you will see the channels themselves and their final result. In some color spaces you will only find one channel. Others, such as CMYK, have four channels. If filters do not work for you, selection areas are not copied, some colors are not included, graphics are not imported from one window to another - urgently check the color mode. Most likely, the image does not have a typical color mode, such as CMYK or Indexed Color.

I'll say even more. If you opened a black and white image, it is very possible that its color mode is Grayscale; if you opened a GIF banner saved from the Internet, its color mode is Indexed Color, since the GIF format is saved only in this mode. If you have a large TIFF file on hand, check the mode, most likely it is CMYK, since TIFFs are usually saved for printing in offset, and the color mode for printing in offset is CMYK. And only one color mode always wins. All filters work in it, colors are displayed, graphics are copied. This color mode is truly the king of modes, since Photoshop itself is designed to work with it. And the name of this mode is RGB. And most images, photographs and other graphics you'll work with will have this color mode. And that's why.

Monitors and RGB

RGB (Red- red, Green- green, Blue- blue) is the most common color model because any modern on-screen luminous devices are based on the RGB color model. Yes, Photoshop can simulate any color space, from CMYK to Lab, but ultimately what we see on the screen is converted to RGB in any case. We work in Photoshop, on the agenda is a printed TIFF file, CMYK color space, in the Chanel channels panel there are four paint channels. But when displaying the work area, the monitor converts them to RGB. Why?

This is how monitors are designed, and this is how almost all luminous screen devices are designed. And then you will understand why. Ultimately, it all comes down to the monitor’s ability to reproduce some colors in principle. In its hardware capabilities, in the quality of its matrix and color gamut coverage. Whatever color space we choose to work in Photoshop, the monitor displays it using RGB. The monitor displays colors as best it can, as well and brightly as the quality of its matrix. So we all end up with our piece of hardware on the table in the end. You can work with excellent color profiles, in flexible color spaces with a wide color gamut, but all is useless if the monitor is bad.

Light and color

To reverse Locke's sayings, there is light and there is color. And light has color. This topic is not the subject of our article, but is necessary for a correct understanding of channels in Photoshop. And especially RGB and CMYK channels. What is light? Light is part of electromagnetic radiation. This is a natural phenomenon that ranks with other electromagnetic radiation such as infrared rays, x-rays, microwaves and ultraviolet radiation. All of them (electromagnetic radiation) are measured in nanometers (nm). Light is measured at 400-700 nm, and I think you can already guess why. Why in the radius from 400 to 700. Is it different? Exactly. And its difference is determined by its color.


Light rays of different colors are measured in different numbers of nanometers, with violet measuring 400 nm, green 550 nm, and red 700 nm. When refracted in a prism, light is split into its component colors: red, orange, green, blue, indigo and violet. Every schoolchild knows this from physics lessons. And based on all that has been said, we can draw simple conclusions that will help us understand the RGB channels:

  • white “light” is the combination of all colors of the spectrum
  • black “light” is the absence of light at all.
  • gradually adding all the colors of the spectrum to each other “brightens” the light until it becomes white
  • the gradual removal of parts of the spectrum “darkens” the light until there is no light left at all.

Surface color

The color of the surface is arranged differently, but is tied to light. We see the color of objects because objects reflect the light falling on them. Different surfaces have different reflective abilities. If a certain surface does not reflect light at all, but absorbs all the rays of the spectrum, then we see black. What else can you see if the object does not reflect light? If the surface reflects all the rays of the spectrum, we see white color. For example, paper reflects all the rays of the spectrum and we see it as white. The moon is white because it reflects the light of the sun, and not because it itself glows purely Samsung Led TV.


Further more. If, for example, a certain surface absorbs all the rays of the spectrum except blue, then this surface looks blue, since it reflects only the blue part of the spectrum. If an object reflects only one part of the spectrum, for example red, then we see it as red. If it reflects the devil and absorbs the devil, then we see the devil. For example, a surface may reflect a little yellow, a little blue, a little green, and absorb everything else. All other, “non-pure” colors consist of this confusion. They are formed by mixing reflected rays of the spectrum. Perhaps this is enough for the theory of color and light. Let's move on to the channels themselves in Photoshop.

Channels in Photoshop for RGB

From pure theory, let's move on to channels in Photoshop. When creating monitors, smart people did not reinvent the wheel. The monitor emits light. The developers took advantage of what Mother Nature offered us and created RGB. How is it built? It consists of 3 channels: red (Red), green (Green) and blue (Blue). When superimposed on each other, the 3 original colors create the composite colors: magenta, cyan and yellow. Together, we get the usual rainbow or spectrum.


The three RGB channels act on each other in the same way that the rays of a spectrum act on each other. When superimposed on each other, a white color is achieved. If all channels are missing, it turns out black, which is logical. Either light or darkness. If one of the channels is missing, one of the composite colors (magenta, cyan or yellow) is obtained. Each RGB channel has a value scale from 0 to 255, where 0 is no light and 255 is the maximum possible light. In our case, this is not white light, but the light of one of the channels, blue, green or red. When all three channels are crossed, taking into account the fact that each channel can have a color gradation, from black to the lightest possible, the entire multi-million color palette in RGB is obtained.


I thought for a long time about how best to depict the overlay of color channels on top of each other, but in such a way as to take into account the gradation of each channel to black, that is, to the absence of light. After some unsuccessful experiments, I depicted them in the form of a flower. Although this flower does not show all possible shades of RGB colors, it does a good job of showing how RGB mixes channels.

RGB channels as a mask option in Photoshop

So what do we know about channels? Already quite a lot. We know that there are three channels in the RGB color space, blue, red and green. We know that when superimposed on each other, composite colors are formed and that each channel has a lightness and darkness parameter from 0 to 255. It's time to look at how an image is generated in RGB.

I open Photoshop, select a beautiful photo and turn on the channels. If you don't know where they are, open Windows > Channels. I will also use the panel Info And Color. They can also be found in the menu Windows. By turning on the channel panel, you will probably see the following picture: one color image, and 3 separate channels with black and white masks, which indicate the degree of illumination of each specific area of ​​​​the photo by a specific channel. If an area in the image is black, then this channel is completely absorbed by the surface; if it is light, it is completely reflected; if it is gray, it is partially absorbed and partially reflected.

You may also see a different picture, color channels instead of black and white. This means absolutely nothing, and does not at all indicate that Photoshop sees everything in color, black and white, or brown-crimson. Photoshop is just a program, it doesn't see anything. It sees the channel values ​​for each pixel and composes the image. Accordingly, the more colorful the photograph, the more it weighs, since there is a lot of information on the color of each pixel, and the more uniform it is, the more single-color pixels, the less the photograph weighs. Because the information on some pixels is repeated. Black and white photographs weigh significantly less than color ones, and a white sheet, compared to a photograph of the same size, weighs nothing at all.



Whether your channels in Photoshop are color or black and white depends solely on the version of Photoshop and the settings installed. If you see black and white channels, go to Edit > Preferences > Interface and check the box Show Chanels in Color. It doesn't make any difference. For color channels, the black area on a particular channel is the zero color intensity value, and the brightest (for example, red, on the red channel) is the maximum channel intensity value of 255. That's all. And also in black and white version. Black - 0 value, white - 255.

In this sense, each channel is a kind of mask, where the black area covers the image, the white area shows, and the gray area half-shows.

Let's consider the operation of channels with black and white images in RGB. For our experiments we will need palettes Color, Channels, Info And Color Picker. Open Color Picker and choose a pure gray color. It is impossible not to notice that in a gray color without tint, the channel values ​​are equal to each other. Which is natural, because if R0 G0 B0 creates a black color (see, the absence of light reflection from the surface), and R255 G255 B255 creates a white color (see, a combination of the entire spectrum, a school prism), then it is logical that with a gradual increase in the values ​​of each channel with an equal value will result in a pure gray color without a hint of tint.

Let's do a little experiment. I opened the photo and using Image > Ajustiments > Desaturate converted it to black and white.

Now I have chosen the tool Color Sampler from the Tools panel and made 4 color proofs in different places of the photo. To display the numerical values ​​of the channels, I will open the Info panel. We see that in all 4 cases the channel values ​​are equal to each other. Let's complicate the task.

I'll go back to the color correction menu and apply the tint filter. Image > Adjustments > Photo Filter In the Filter panel, I'll select the pure blue color R0 G0 B255 and tone the photo slightly.

As you can see, the hue of the photo has changed, although it is still perceived as B&W. Let's look at our color swatches in the Info panel. The red and green channel values ​​remain unchanged. And the value of the blue channel exceeded the values ​​of the red and green. Due to this, the black and white photograph received its bluish tint, because the intensity of the blue channel exceeds the other two. I achieved clean results by using a pure blue R0 G0 B255 with zero values ​​for the red and green channels when color grading. If I had used a shade that was not entirely pure, for example R10 G15 B250, then my values ​​would not have been even. In this case, the filter would also affect the Red and Green channels, but the photo would still get its blue tint, since the value of the blue channel would be a hundred times higher than the others.


Channels in Photoshop and sepia

How is the Sepia effect created? The photo is still black and white. It just has a yellowish tint. How does RGB create the color yellow? Known as when superimposing Red on Green. That is, R255 G255 B0

Open a black and white photo Apply the effect Image > Adjustments > Photo Filter, but this time we will use the pure yellow color R255 G255 B0. It's not hard to guess what we'll get in the Info panel.

The values ​​of the Red and Green channels increased evenly, while the values ​​of the Blue channel remained unchanged. Due to this, the photo received a yellowish tint. Now that you understand the nature of RGB channels, let's look at a color image.

Channels in Photoshop and color image

With a black and white image everything is simple. In each area of ​​the image, all channels are equal to each other. The values ​​are of course different due to the degree of lightness and darkness, but all three channels are always synchronous with each other. With color images everything is different. Each pixel in a color image contains different information on all three channels. That's why it's colored. Due to this, a color image weighs more than a black and white image. Let's look at our photo.

The conditions are the same. Already a color photograph, the previous 4 color samples. 1) In the sky, 2) on the clouds, 3) on the dark part of the clouds and 4) on the tree. Let's see what's happening in the sky. In a section of the sky, the channel values ​​are 0 in the red channel, 56 in the green channel and 134 in the blue channel. The red channel is missing and we do not see it. 134 blue gives a pure dark blue color. And 56 of the green channel adds brightness towards the blue. As you remember, R0 G255 B255 give a bright blue color. The result is a blue sky, where the blue channel creates a dark blue tone, and the green lightens it towards blue.

The second value is the light part of the cloud. In the Info panel the values ​​are 240 for red, 243 for green and 247 for blue. The first thing that catches your eye is that the values ​​are extremely equal. This means the color will be close to grayscale. In our case, the values ​​are not only equal, but also high. From 240 to 247. Almost a maximum of 255, which indicates that the color will be almost white. And so it is. The clouds are extremely white. Now let's look at the shade. The values ​​are almost equal, but not completely. Blue channel 247 is higher than red, by 7 points. The green channel is also higher by 3 points. As you remember, 255 Green and 255 Blue give blue. This means the color will have a slightly bluish tint. And so it is.

In the third area, I selected the shadowed part of the cloud. First of all, we see that the values ​​are also high. 166 on red, 182 on green, 208 on blue. The values ​​indicate that this color is also quite light. But not as light as in the second sample. Light gray, and higher blue and green channel values ​​give light gray a distinct blue tint.

On the tree section, the values ​​are 3 for red, 23 for green, 16 for blue channels. The values ​​tend to zero, which indicates that the color is almost black. And so it is, the tree is really dark. As usual, the red channel is minimal; the green and blue channels win throughout the photo. Except, of course, grass, but more on that later. In this area, the green channel is significantly higher than the blue one, and accordingly the tree receives a dark greenish tone.

And a few more examples. I made two final marks on the light and dark parts of the grass. In this case, the blue channel plays. Its value is low. Red and green win. As you remember, the red and green channels give pure yellow. In our case, the red channel is not enough to switch the green channel to yellow, so the color goes towards the yellow-green swamp. But the green channel is not at its full maximum capabilities, if its value were inferior to the red one, the grass would have a reddish tint, but the green channel is stronger, and the grass is greenish. The blue channel also adds a slight tone, although it is almost imperceptible.

In our latest battle, the green channel is the clear winner. Its value is 137, half power, so the color is not bright but quite dark. The red channel tries to shift the hue towards orange, but to no avail. The blue channel is practically disabled.

And so each color section is added using RGB channels. The essence of the channel is a light intensity mask for each area of ​​the image. In the sky area, the red channel is black, which means the color consists of green and blue channels. There is no blue channel in the grass area. Green looks brighter than red, which means the grass will be mostly green. I hope you get the idea.

Reading channels by mask

This is what I want to achieve from you. I want you to understand that the channel image is a mask, where dark places mean the absence of the channel's action, and light places mean the effect of the channel's tone. Take our image as an example. You can understand the color of a photograph without seeing the colors. It can be read based on the channel masks. Now we will learn how to do this by deciphering the logic of color mixing in RGB.

The photo shows the sky, a tree, and a field. Let's see what the channels show. On the red channel the sky is completely black. This means that there is no effect of red in this area. The blue and green channels remain. On the blue channel, the color of the sky is clearly lighter, which means the action of the blue channel is higher here. But the green channel also makes its contribution. As you remember, the blue and green channels give blue. We get a light blue sky, darker towards the upper right corner, since the effect of green is noticeably weakened there.

Let's consider the field. The blue channel in this area is almost black. The brightest area is near the red channel, which is rivaled only by the green channel. Which means the field is yellow. Gradations on the green value move the color towards orange and dark red.

Let's look at the tree. On all masks its color is almost the same. This means the tree is quite colorless, close to gray. But still, on the red channel the tree is much lighter, and on the blue channel, it is darker. This indicates that the shade of the wood is red. In our case, the red is so strong that it reduced the gray to brown.

RGB and Screen mode

We can simulate RGB channel mixing ourselves. This is how I created most of the illustrations for this article. Draw ellipses on different layers, fill them with pure colors. Pure blue R0 G0 B255, pure green R0 G255 B0 and pure red R255 G0 B0. In the Windows Layers panel > Layers, change the layers' blending modes to Screen. The Screen blend mode cuts out dark pixels, favoring light pixels. But it also mixes different pixel tones in the same way it mixes their RGB color model.

I tried to write as concisely as possible, but the article turned out to be too lengthy. But now you fully understand how RGB channels are arranged in Photoshop, and not only in Photoshop. They are built the same everywhere, believe me. I will develop the topic of channels in my next articles on this topic. In the following parts I will describe the channels in CMYK and Lab, and also move on to their practical use in color correction and printing.


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Many people are probably wondering what sRGB is in camera settings, why is it needed and what is better, sRGB or Adobe RGB?

RGB is an abbreviation for the names of primary colors (Red, Green, Blue). Why are they basic? Because humans, unlike some other species, have trichromatic vision. That is, there are receptors in the eye that are sensitive to these three colors. Our brain makes a huge contribution to the perception of color, so the task of correctly displaying color is non-trivial and requires significant tricks.

Color space is the set of colors that we can observe or display. There are many ways to display color spaces graphically, but clever mathematicians have come up with one very elegant way that you see all the time on the Internet.

The concept of color can be represented as follows: color consists of two components - brightness and tonality. That is, gray differs from white only in brightness; they have the same tonality. As a result of experiments at the beginning of the 20th century, it was possible to determine the range of colors that are perceived by humans. Using mathematical transformations, the entire set of tones was displayed on a plane, and this diagram was called CIE 1931 (1931 is the year when the diagram was presented). Thus, it became possible to describe color by x,y coordinates on a graph, plus brightness.

The colors shown in the diagram are for illustrative purposes; these are not the colors you see in everyday life.

There have never been any particular problems with color registration; any digital camera has a color gamut that the sensor sees that is much wider than what a person can see. This is partly why infrared and ultraviolet filters are used inside the camera to simplify subsequent signal processing.

There were problems with color display, especially on the monitor screen. The capabilities of displays are severely limited due to physical reasons, and obtaining the full range of colors that the human brain distinguishes was practically impossible. There have been many attempts to create a color display that displays most shades, but a compromise between color reproduction and device price was achieved in the 50s with CRT displays.

To curb the variety of color displays and make professional image processing on a computer more predictable, the sRGB standard was developed in the 90s. It appeared as a result of an analysis of the capabilities of the most common CRT (CRT) monitors at that time. At that time, no one even dreamed of LCD displays; moreover, in terms of characteristics and price, LCDs lagged far behind CRTs and could not be the basis for a standard.

The operating principle of CRT screens is simple - by mixing three primary colors (red, green, blue), various shades are obtained. Two problems:

  1. the number of shades available depends on the purity of the primary colors, and pure colors are very difficult to achieve
  2. You can't get all the visible colors just by mixing the three primary colors.

The sRGB standard describes exactly what purity the primary colors should be and what shades are achievable when mixed. It also determines where the white point is. On the CIE diagram, the sRGB standard looks like a triangle with the coordinates of the primary colors at the vertices:

It is easy to see how modest the capabilities of technology are compared to what nature has endowed us with.

Even if you get primary colors of exceptional purity, as is achieved with laser displays, you will not get the full color gamut that we see in the world around us. Everything that such a display is capable of is limited by the triangle:

By the way, when printing there are no such strict restrictions on the number of primary color sources, and therefore, for quite reasonable money, cool photo printers use, for example, 8-color printing. At the same time, the color gamut is expanded at a not very high cost and looks like a polygon on the diagram. Here's what the color gamut of a not-so-cool printer looks like compared to sRGB:

But printers have a lot of other problems, in particular, the dependence of color rendering on paper quality and so on.

Adobe RGB is a different but very similar standard, it is slightly wider and covers more colors:

You'll probably want to immediately run and switch your camera's sRGB to Adobe RGB, but don't rush to do it.

Adobe RGB is only needed by those who print professionally and know exactly what they are doing (such people do not need to read our articles). The vast majority of screens and programs work in the sRGB standard and know nothing about Adobe RGB, this is how it happened historically. Moreover, if you try to display Adobe RGB colors on an sRGB screen, color rendering problems may occur. sRGB ensures that at least most people will see roughly the same colors as you.

Due to the limited sRGB range, you've probably noticed that after photographing a red rose, you can't distinguish the petals in the photo. The screen's capabilities are simply not enough to depict all the details in shades of red, for example.

Of course, a lot depends on the monitor settings, so photographers prefer to deal with monitors on IPS matrices and look for models that are calibrated at the factory, such as LG IPS236V. All manufacturers try to comply with the sRGB standard, some do better, some do worse.

Recently, technology has advanced greatly and LCD monitors sometimes show a color gamut even wider than CRT monitors, although until recently this was not possible, which is why the old bulky screens could not be forced out of design departments for a long time. Here is the color gamut of a professional LCD monitor:

Our attentive readers have probably already exhausted themselves with the question of what kind of diagram is in the title of the article, what monitor is it from? This is not a monitor, but a Samsung Galaxy Note phone. The trick is that modern smartphones use a new display technology - AMOLED (organic light-emitting diodes). So far, full-fledged large AMOLED monitors are very expensive, but I believe that the future lies with them.

AMOLED allows you to achieve purer primary colors and, as a result, a wider color gamut. In practice, this means that the picture on the Samsung Galaxy Note will be richer and more contrasty than on the screens of previous generations.

Thank you for your attention.

Why are different color models needed and why the same color can look different

Providing design services both in the field of web and in the field of printing, we often come across a question from the Client: why do the same corporate colors in the design layout of the website and in the design layout of printed products look different? The answer to this question lies in the differences between color models: digital and printed.

The color of a computer screen varies from black (no color) to white (the maximum brightness of all components of color: red, green and blue). On paper, on the contrary, the absence of color corresponds to white, and the mixing of the maximum number of colors corresponds to dark brown, which is perceived as black.

Therefore, when preparing for printing, the image must be converted from additive ("folding") flower models RGB into subtractive (“subtractive”) CMYK model. The CMYK model uses the opposite colors of the original colors - the opposite of red is cyan, the opposite of green is magenta, and the opposite of blue is yellow.

Digital RGB color model

What is RGB?

The abbreviation RGB means the names of three colors used to display a color image on the screen: Red (red), Green (green), Blue (blue).

How is RGB color formed?

The color on the monitor screen is formed by combining rays of three primary colors - red, green and blue. If the intensity of each of them reaches 100%, then the color white is obtained. The absence of all three colors produces black.

Thus, any color that we see on the screen can be described by three numbers indicating the brightness of the red, green and blue color components in the digital range from 0 to 255. Graphics programs allow you to combine the required RGB color from 256 shades of red, 256 shades of green and 256 shades of blue. The total is 256 x 256 x 256 = 16.7 million colors.

Where are RGB images used?

RGB images are used to display on a monitor screen. When creating colors for viewing in browsers, the same RGB color model is used as a basis.

Printing color model CMYK

What is CMYK?

The CMYK system is created and used for typographic printing. The abbreviation CMYK stands for the names of the primary inks used for four-color printing: cyan (Cyan), magenta (Magenta) and yellow (Yellow). The letter K stands for black ink (BlacK), which allows you to achieve a rich black color when printing. The last letter of the word is used, not the first, to avoid confusion between Black and Blue.

How is CMYK color formed?

Each of the numbers that define a color in CMYK represents the percentage of paint of that color that makes up the color combination. For example, to obtain a dark orange color, you would mix 30% cyan paint, 45% magenta paint, 80% yellow paint and 5% black paint. This can be expressed as follows: (30/45/80/5).

Where are CMYK images used?

The scope of application of the CMYK color model is full-color printing. It is this model that most printing devices work with. Due to color model mismatches, there is often a situation where the color you want to print cannot be reproduced using the CMYK model (for example, gold or silver).

In this case, Pantone inks are used (ready-made mixed inks of many colors and shades), they are also called spot inks (since these inks are not mixed during printing, but are opaque).

All files intended for printing must be converted to CMYK. This process is called color separation. RGB covers a larger color range than CMYK, and this must be taken into account when creating images that you later plan to print on a printer or printing house.

When viewing a CMYK image on a monitor screen, the same colors may appear slightly differently than when viewing an RGB image. The CMYK model cannot display the very bright colors of the RGB model; the RGB model, in turn, is not able to convey the dark, dense shades of the CMYK model, since the nature of the color is different.

The color display on your monitor screen changes frequently and depends on lighting conditions, monitor temperature, and the color of surrounding objects. In addition, many colors seen in real life cannot be output when printed, not all colors displayed on screen can be printed, and some print colors are not visible on a monitor screen.

Thus, when preparing a company logo for publication on the website, we use the RGB model. When preparing the same logo for printing in a printing house (for example, on business cards or letterhead), we use a CMYK model, and the colors of this model on the screen may be visually slightly different from those we see in RGB. There is no need to be afraid of this: after all, on paper, the colors of the logo will closely match the colors that we see on the screen.