Photoshop Color theory

Color stimulates people's feelings; it produces contrasting effects, making the image look more beautiful. It can make a dark image bright and gorgeous, so that a lifeless image full of vitality. For graphic designers, painters, artists, or video producers, creating the perfect color is critical. When the use of color is not correct, the concept of expression is incomplete, the image may not be able to successfully express its information, artistic experience is lost. If a picture of a forest that should be green lush green is yellow and sickly, then the importance of nature is not reflected, and the "health" of the outdoors is gone. If the glowing red glow in the forest flames darkens, it conveys a feeling of decay and rust, not a warm feeling. It's not easy to create the perfect color. The painter must mix and then mix the pigments until the color of the image is exactly the same as what is seen or imagined. Photographers and filmmakers must spend a lot of time testing, resetting the focus and increasing the light until a proper landscape is created.

In many ways, using colors on your computer is no different. The computer forms its own set of special complexities and technical difficulties. How do users make sure that the colors they see on the screen match those of the natural or user art imagination? Also, how do you make the color that you see on the screen the color that prints the image output? To create a suitable color in Photoshop, you must first have some knowledge of the color theory. Once the user understands the basics of color theory, it will recognize the color terminology used in dialog boxes, menus, and palettes throughout Photoshop. When the user is in the color correction (colour correcting), will also be irresolute and subtractive process. With the knowledge of color theory, users will know how to colour the sky with a plump, full-bodied blue. The user will be able to pick colors (pickcolors) so that the Emerald Lust drop PEI Green created in Photoshop appears in the forest on the printed paper.

In order to successfully select the correct color in Photoshop, the user must first understand the color mode. Creating a C olor Modeis (color mode) is used to provide a way to translate colors into digital data so that colors can be continuously described in a variety of media. For example, when we refer to a "blue-green" color, the understanding of this color depends to a large extent on the individual's feelings. On the other hand, if we give it a proprietary color value in a color pattern--100% cyan in CMYK mode, 3% Magenta, 3o% yellow, and 15% black--it is possible to produce the same color constantly.

When users use the Phtotoshop color feature, they will encounter several different color modes: Rgb,cmy K, HSB, and Lab. RGB and CMYK color modes let users always remember the natural color, and the colors on the user monitor and the colors on the printed paper are created in a completely different way. The monitor is created by emitting red, green, and blue light Shilai: It uses the RGB (Red/green/blue) color mode. To reproduce the effect of a continuous color on a color photograph, the printing technique uses a combination of cyan, magenta, yellow, and black ink to reflect and absorb light waves of all kinds. The colors created by adding the four colors (overprint) are part of the CMYK (cyan/Magenta/yellow/black) color pattern. HSB (color/saturation/brightness) color patterns are based on the way people feel color, thus providing an intuitive way to translate natural colors into colors created by users ' computers. Lab color mode provides a way to create a color that is not dependent on devices, which means that lab colors cannot be changed regardless of which monitor or printer is being used.

1. What is color

The color exists because there are three entities: light, the object being viewed, and the observer. Physicists have shown that white light is made up of three wavelengths, red, green and blue. The human eye is formed by the color as red, green, and blue, which are absorbed or reflected by different wavelengths of the object. For example, suppose that a user is enrolled in a wild sutra on a clear day and is preparing to take a red apple. The sun shines on the apple, and the red wavelength of light is reflected in the user's eye from the apple. The green and blue wavelengths are absorbed by the apples. The sensor in the user's eye responds to the reflected light and launches the message, which is interpreted by the user's brain as red. The user's sense of red depends on the apple, the light, and itself. An apple may absorb more green and blue than another apple, so its color looks redder. If the clouds cover the sun, the red of the apple becomes dim. Users ' feelings about the Apple are also influenced by their own physical conditions, the experience of eating an apple, or the fact that they have not eaten all day. Enabling users to see the red, green, and blue wavelengths of Apple are the basis of all colors in nature. That is why we often call red, green, and blue three colors the color of the light. All colors in the spectrum are composed of different intensities of these three wavelengths. By overlapping the three base colors, they produce a secondary blend color: cyan, magenta, and yellow. The base color and the secondary blend color are complementary colors of each other. Complementary c olors (complementary color) is the most different color between each other. Yellow is made up of red and green. Where Blue is a primary color that is missing, so blue and yellow are complementary colors. The complementary color of green is magenta, the complementary color of red is cyan. This is why users can see other colors beyond the Chenhong, green, and blue colours. In a solar flower, the user sees yellow because the red and green wavelengths are reflected in the user's eyes, while the blue is absorbed by the sun's flowers. The mixture of all the base colors forms a white. Users may think that adding these colors together will create a darker color, but don't forget that we add light. When we add the wavelength of light together, we get a brighter color. This is why the base color is often referred to as adding color (addi tive clors). By adding all the colors of light to the ~, we get the brightest light: white light. So when we see a piece of white paper, all the red, green, and blue wavelengths are reflected in our eyes. When we see black, all the red, green, and blue wavelengths are completely absorbed by the object, so there is no light reflected in our eyes.

2. RGB color Mode

The system for creating colors on the monitor is based on the same basic characteristics as light in nature: Colors can be produced by three wavelengths, red, green, and blue. This is the basis of the RGB color pattern.

A monitor is a beam of three different intensities that glows red, green, and blue phosphorescent material on the inside of the screen to produce color. When the user sees red in Photoshop, the monitor has turned on its red beam, and the red beam stimulates the red phosphorescent material, which lights out a red pixel on the screen. Therefore, watching an Apple scan on the screen is not the same as watching an apple on the top of the computer to eat. When the user closes the indoor lights, they will not see their red fast food, but the user can still see the apple scan image, because the light is emitted from the monitor.

In the RGB color mode of Photoshop, you can change the color of pixels by combining various values of red, green, and blue. Each of these three base colors has a range of values from O to 255. When a user combines 256 red values, 256 green values, and 256 blue values, all the colors that can be obtained are about 1. 670 million (256 x 256 x 256) species. It looks like it's already a lot of colors, but don't forget, these are just a few of the colors that are visible in nature. However, 1. The 670 million colors are sufficient to replicate crystal-clear digitized images on a monitor that is connected to a computer that is equipped with a 24-bit color.

In this section, the user will use the RGB color on the picker and swatches palettes. Users will see how colors are created from RGB color values and learn how to mix colors by setting an RGB color value. If Picker and SW. Tches Palette is not open, now select Show Picker from the Window/palette submenu to open the Picker/swatches/scratch group. Because the user needs to open two palettes at the same time, the picker palette is separated from the Picker/swatches/scratch group by tapping and dragging the mouse over the palette group on the Picker palette.

If the swatches palette is not in the group where the Picker palette is located, select Show swatches in the Win-dow/palette submenu. By default, the Picker palette will display the RGB color mode palette unless it has been changed in the previous section. The user will see three bars, called Clor sliders (color sliders), labeled R,g and B. If the user does not see the letters R, G, and B, the user is in a different color mode palette. The Picker palette pop-up can be tapped to change to an RGB palette. A list of Photoshop color patterns will be displayed on the screen. Select the RGB Slides in the list, then the palette with three RGB sliders is loaded. At the bottom of each adjuster is a triangle with a slider control block (Slider controls). The user can tap and drag the mouse on the controller to "change the value of red, green, and blue colors in the foreground or background colors." The foreground and background colors are displayed in the selection boxes (the overlapping squares in the upper-right corner of the P icker palette).

Note that the Pick palette also shows a horizontal color bar along the bottom of the palette. By default, the bar displays the RGB color spectra or gamut. You can set the bar to an RGB spectrum by tapping the palette's pop-up menu arrow and selecting the Color bar. The Color Bar dialog box is displayed. The style pop-up menu in the dialog box allows users to choose between RGB-CMYK color spectral bars. The user can also have the color bar display a gradient color that transitions from black to white or from the foreground to the background color. If the Style menu is not set to RGB Spectrum, the user will need to select the RGB Sp Ecturm in the list of options to reset it.

Users can use Colorbar to quickly pick a foreground or background color. What the user needs to do is just tap the mouse on the bar, and in the next section, the user will use the Swatches palette to pick the colors more precisely. d Note Selecting foreground to Background style in the Color Bar dialog box activates the L ock to currentcolors (fixed on the current color) check box. When this option is selected, if a new foreground or background color is selected, the foreground to background color bar in the picker palette will not change.

1. Use swatches (sample) to pick colors

First in the Swatches palette, hit the red, green, blue squares, or samples, and check the values of these base colors. This will sample the full range of each color component in the RGB color pattern. When the user knocks on a sample, the Photo shop displays the sample color in the foreground or background checkbox and displays its r,g,b value on the right side of the slider control block in the picker palette. Note To see the foreground or background color in each slider control block, the user must activate the dynamic Sliders (animated slider) option for Photoshop. When the dymamic sliders option is activated, each slider displays the foreground or background color above the slider control block (Slider). If the user does not start the Dynamic sliders option, each slider displays only the color values of the red, green, or blue components. The user can select General in the File/preference S submenu to start Dynamic sliders. Tap the M ore button in the General Prehrences dialog box. In the More Preferences dialog box, select the Dynamic sliders check box.

In this exercise, the user will only use the Phtoshop foreground color. Before you begin, the user must make sure that the FO re-ground check box (the one square above the two interactive overlapping squares on the right side of the slider in the Picker palette) is activated. If the white border is not around the foreground check box, click on the box to activate the foreground color. To view the RGB value of the red color, place the mouse pointer over the red sample on the first line of the upper-left corner of the color sample. When the pointer turns into an eyedropper, tap the Red sample. In the Picker palette, note that the R slider control jumps to the right end. The number on the right side of the slider indicates the red value of the color sample that the user has just struck (the value should be 25 5 if the user taps the correct red color). The activity color (foreground view) in the Photo shop has now become the red value. Look at the green and blue drops: they all have a value of 0, because the red color that the user is tapping does not contain any green or blue components. To see the RGB value of a subordinate base color, tap the Green sample (located on the first row of the swatches palette from the third position on the left), the G value in the picker palette jumps to 255, while the blue and red values fall to 0. To see the value of the Ottolenghi color, the first row in the Swatches palette is clicked from the fifth color sample on the left. The color value of pure blue is 255 and does not contain any red or green ingredients. From the previous experiments on these color samples, we can see that each of the base colors has a range of color values ranging from 0 to 255, producing 256 independent color values.

2. Use the slider to create an RGB color

Now that the user has seen the color values of the three colors, pure red, pure green, and blue, let's look at some of the other colors that come out of these base colours. By tapping any color swatch in the Switches palette, the user will see a combination of its RGB color-planting. The user can try a yellow color, which is located on row fourth, column fourth. Note the combination of their color-planting: r255,g236 and B103. Tap on some of the other color samples and note the combination of three base colors. Of course, the color Swatch palette cannot contain all 1. 670 million colors, but by using the mouse to adjust the slider control block, the user can create the 1 that photohop can display. Any of the 670 million colors.

All three kinds of sliders work in the same way. More colors are added when the user clicks and drags the slider control block to the right. When the user drags the control block to the left, the color is reduced. The user can select any one of the color samples and try to drag the G-Slider control block from left to right. Note that as the user drags the control block to the right, the green color value increases gradually, and the foreground color created by the user in the Picker palette is becoming brighter. Now drag the control block to the left, and as the user moves the control block to the right, the green value is reduced and the green is fading.

To create a black, drag all the slider control blocks to the left and set them to O. The user can see that the foreground color in the picker palette darkens gradually. When all the color values are up to O, the foreground color appears black. If the color values of red, green, and blue are exactly equal but not O or 255, then a gray is created.

To create white, all slider control blocks are moved in the opposite direction. By doing so, the user increases the light. Set each slider to its maximum value of 255 to create white.

3. Use the slider to display RGB complementary colors

If the user is using the Dynamic sliders option, when all the RGB sliders are set to 255, the user will see a color range on each slider. The R slider shows the transition from white to cyan; The G slider shows the shift from white to magenta, while the B slider shows changes from white to yellow. Why does the slider change color? Photoshop's designers are smart enough to remind users to think about color theory. In each slider, the user sees the opposing color (its complementary color) of each base color. The color of each slider gradually tends to the left to tell the user: if he subtracts a base color from white (by dragging the slider control block to the left), what happens. Remember the previous discussion about why when we saw a sun flower we saw a yellow. Sun-Flower? The solar flower absorbs (minus) the blue wavelength in the light. When red and green are reflected in our eyes, we see yellow. Users can easily prove this with the slider. To create a yellow, or blue, complementary color, drag the B-slider control block back to O and keep the R and G sliders set to 2 5 5. In this way, by subtracting the blue from the white, the user builds the yellow with Chuang Chuang. To create cyan, a red complementary color, you can first set all the slider control blocks to 255, and then drag the R slider control block back to the O. By subtracting the red value from the base color, the user creates the cyan. To create a magenta, or green, complementary color, drag the R slider control block to 255 and drag the G slider control block back to 0. In this way, the user creates the magenta by subtracting the green value from the base color.

This subtractive concept is the basis of the CMYK color pattern, and the following sections discuss the CMYK color patterns.

3.CMYK Color Mode

The basis of the

CMYK color mode is not to increase the light, but to subtract the light. In RGB mode, the creation of colors is achieved by adding light; a monitor (or a TV) is a light source that creates colors. But a sheet of paper does not emit light; it absorbs and reflects only light. Therefore, when the user wants to convert the color of the monitor to the paper, it is necessary to use another color mode Cmyk,cmyk is the basis of the four-color printing, the four-color processing printing is mainly used in the printing presses on the color of the continuous image (such as digital photo-back film). In the process of four-color processing, the color is produced by using four different four printing rights on a printing press (printing), and these four different printed boards are C (cyan Green), M (magenta magenta), Y (yellow yellow) and back. K (black blacks are represented by K because B may also represent Blue blue). Because the printed paper cannot emit light, the printing press cannot use RGB colors to print; Instead, it uses some inks that absorb specific wavelengths of light to reflect other wavelengths. By combining cyan, magenta, and yellow inks, a commercial printing press is able to replicate the most important parts of the visible spectrum color. In theory, you must combine 100% cyan, ioo% Magenta, and 100% yellow to produce black. However, because the ink is impure, cyan, magenta and yellow color is not black, but a fuzzy brown. Therefore, printing workers usually add black in cyan, magenta, and yellow to produce dark and gray portions of the image. Note that each of the two subtractive blends produces a base color. To introduce to the user what CMYK color mode is, let's first switch to the CMYK color spectrum. To do this, the user clicks the mouse on the pop-up menu arrow in the Picker palette and then selects Color Bar in the pop-up list. When the Color Bar dialog box opens, select C Myk Spectrum in the Style pop-up menu. The user may notice that the CMYK color is darker than the RGB color.

Now let's take a look at how to use the CMYK slider in the Picker palette to change the color. First, the user needs to tap the mouse on the pop-up menu arrows of the Picker palette to switch to the CMYK color slider. The MAC user drags the mouse to the CMYK Sliders option (PC User: Tapping the mouse on the CMYK sliders). On the picker palette, users will also see some differences between RGB and CMYK palettes. First, CMYK uses four sliders instead of three. Every kind of subtractive has a slip: C is for Cyan, M is for magenta, y is for yellow, K is for black. Also, these colors are measured in percentages. Percentages provide a standard way to transfer various ink color values from the design room to the printing press. Using CMYK percentages may be confusing, but it can help users understand this by using a CMYK percentage to produce the base color. When users know how to produce red, green, and blue from CMYK values, they can better grasp the sense when mixing colors or modifying colors in this color pattern. In order to help users create these colors, it is useful to have a color wheel in hand (colour wheel).

In a color wheel, colors are arranged in a circle to show the relationship between each other. The base colors are arranged in circles and are exactly the same distance from each other. Each of the secondary colors is located between the two base colors. By this arrangement, each color is directly relative to its own complementary color, and each color in the wheel is between the two colors that produce it. By learning the color wheel, the user can see the yellow and magenta added together to produce red. If the user subtracts yellow and magenta, the red is erased. In this way, if the user wants to subtract red from an image, only reduce the yellow and magenta percentages. Another thing to keep in mind is that in a color, if the user adds color to an image, it is actually subtracting its complementary color. For example, when a user dyes an image more red, in fact he is reducing the percentage of cyan (cyan is a red complementary color, in the color wheel directly relative to each other). 2 Use the slider to create a CMYK color

Now the user will practice using the color wheel and the CMYK slider to create red, green, and blue. This simple example will show how CMYK inks absorb different light waves and reflect other light waves to produce color. To create red, first drag the red and yellow to the 1oo%, while the cyan and black are left at the o% place. Note that red is located between the yellow and magenta in the color wheel. When a user sees a red color in an image that is printed with a four-color process, it means that the yellow and magenta inks combine to absorb the blue and green waves in the light. The result is red. To create green, drag the yellow and cyan to the 1oo%, leaving magenta and black at the o%. Green is between yellow and cyan in the color wheel. When a user sees a color that is green in the image that is being used to process the print, the yellow and cyan inks are combined to absorb the blue and red light waves. To create blue, drag cyan and magenta to 1oo%, leaving yellow and black at 0%. Blue is between cyan and magenta on the color wheel. When a user sees a blue color in an image that is printed with a four-colour process, the cyan and magenta inks are combined to absorb the red and green wavelengths.

Now try using the slider to create an extra mcyk color. If the user has a sample book showing the CMYK percentages and the colors they produce, you can use the slider to copy some of the colors and see how the screen colors resemble the colors of the real objects. Note If the user is interested in creating and printing a four-color separation (four-color separations), the user's file mode must be CYMK.

3. 3 Beyond the Spectrum (Out-of-gamut) warning

Before we leave the CMYK color pattern to the next section, it is important to know that the RGB and CMYK color patterns are not the same color spectrum. The visible color range of a color pattern is in the jargon gamut spectrum. RGB spectrum is larger than the CMYK spectrum, so if users only use the RGB color on the computer, you should pay attention to the design and editing of the screen color is not able to print out.

Fortunately, Photoshop gives a warning when the user is out of range of printable colors. The user may have noticed this warning: it is a small warning sign--a triangle with an exclamation point--that appears on top of the picker palette. Even if the user is using the CMYK slider, you can activate Alert (alarm) by tapping any of the six color samples from the left in the top row.

For example, a user can tap the Red sample in the first row of the swatches palette. The alert symbol is immediately displayed, indicating that the color is beyond the CMYK spectral range. If the user knocks on an alert, Photoshop will choose the closest printable color. Now the user can tap the Aiert, and the closest printable red will appear as the foreground color. However, even if Photoshop tells the user that this is a printable red, it only shows a red analog color for the RGB monitor. Never expect the color that the user sees on the screen to be the color of the printed result. Note If the user is in a CMYK color file and wants to use a color beyond the spectral range, Photoshop will convert it to the closest printed color. Before converting an RGB color image to a CMYK color image, Photoshop can also advance all colors beyond the spectral range.