Lessons Photoshop. Topic 4. Color correction. Lesson 3. Change color with the Hue / Saturation tool
Adobe Photoshop is one of the most popular packages for processing bitmap graphics. Despite the high price, up to 80% of professional designers, photographers, and computer graphics artists use the program. Due to its enormous functionality and ease of use, Adobe Photoshop has a dominant position in the graphics editor market. Color grading with the Hue / Saturation tool.About Adobe Photoshop Rich tools and ease of use make the program convenient for both simple photo correction and for creating complex images. Adobe Photoshop owes much of its position in the market to the wealth, power and simplicity of tools for changing the color of images - color correction. The task seems difficult only at first glance. In fact, it turns out to be easily solvable even for a beginner. The main thing is to decide what to do and choose the right tool. Topic 4. Color Correction Lesson 3. Changing color using the Hue / Saturation tool.The invention of color photography and the technologies that made it accessible have revolutionized human relationships. Memory, feelings, relationships - all this is impossible to imagine without a photo. Digital technology has only increased the effect. They also provided great opportunities for creativity. With some tools and knowledge, even the most unsuccessful, “defective” photo can be turned into a bright, memorable picture. With tools it is clear - you are reading this lesson. This means that Adobe Photoshop (any version: from 6.5 to CS6) is installed on your computer. As for knowledge, the lack of it is fixable. Including a lesson that the author has the honor to offer you. In this lesson, we'll talk about the most delicate method for changing the color of a photo. In most cases, color correction is reduced to increasing or decreasing the presence of individual tones in the image. Having studied the channels and the theory of light, we understand that such a process inevitably affects other parameters. For example, sharpness. It is easy to verify this. Read the tutorials on “how to sharpen with channels” and “how to create high-quality black and white photography from color.” However, there is a tool that can change the color of your image without affecting other parameters. This is hue / saturation. Some of his work has already been described in one of the previous lessons. It's time to analyze the work in more detail. Some theory
Let's talk about something else - the HSB space, or as it is also called HSV . Is it unfamiliar? However, each of you has used it. For example, when choosing a text color in office programs. The idea of the HSB color space was formulated by Alvy Ray Smith in 1974. This is the same Smith who founded Pixar in 1986. Back in the 70s, Alvy Rae was developing the first graphics editor - SuperPaint. It was then that the discourse arose - how to encode colors digitally. When developing the HSB color space, Smith drew on "natural" color perception methods. We are used to distinguishing between base colors. And the shades are perceived as a certain tone and saturation of the main color. If we add here the difference in color perception at different times of the day (we don't see colors in the dark), a third parameter is added - the amount of light. This is HSB. Where H (Hue) is the color tone. Or, in the language of physics, the wavelength of light. S (Saturation) - saturation. Or, again remembering the natural sciences, the intensity of the wave. The last parameter is called Brightness. Sometimes referred to as Value . This is the brightness or amount of light. The basic "scientific" graphical representation of HSB looks like either cake or diamond. Where is the cycle of the main shades of light located on the circle. The central axis is gray scale. Accordingly, the saturation axis goes from the edge (bright color) to the center (black and white projection of the color). And the illumination axis is located "vertically". At the bottom - deep black. Given that we do not recognize shades in low light (they merge into black), the cake is portrayed as a "diamond". An example is at the bottom of the illustration. However, we are more used to one-dimensional projections of space. Look at the top two parts of the picture. It's like a cut paper ring. The color on the edges is the same. Inside - all the wealth of the rainbow. In the case of the "rectangle", a vertical scale of brightness or amount of color has been added. How does it work?Everything is simple here. Remember the volume knobs on older audio devices. You twist the knob, changing the position of the scale relative to the stationary notch on the body. The HSB space works in a similar way. Place a notch in your mind near any part of the "cone" and mark the color. Twist: the marked color will be replaced by the one opposite your mental serif. Practical partThe Hue / Saturation palette is very close in philosophy to the HSB space (HSV). The difference is in the last letter and the function it stands for. In HSB, Brightness (or Value) means a scale from black to no black. That is, the minimum values are black. Maximum - full saturation of the hue without the presence of black. Therefore, the scale is translated as both brightness and amount of light. In the model used by the Hue / Saturation tool, the third scale in USA translation is called brightness. But in the original (in English) it is referred to as Lightness. This word has another translation - lordship. Minimum values are a black rectangle instead of an image. Maximum - full exposure - bright white. You can call the hue / saturation palette from the " Image " - " Correction " menu or the CTRL + U hotkey combination.
To illustrate the work, let's take a photo of the Kiev architectural monument - "houses with chimeras". Call the tool as above. The palette, as with the Levels and Curves tools, lets you apply predefined application settings. To do this, just select one of the options in the drop-down menu " Style ".
The second drop-down menu is a selection of a color range that can be changed. The options include 6 base colors for RGB and CMYK models. We will talk about how to work with a separate range in one of the following lessons. Next, notice the two bands of the color wheel projection (at the bottom of the panel. In the illustration, they are designated by numbers 1 and 2). The points on the far left and right represent the same color. Top (number 1) is the reference position of the color wheel. The bottom one (number 2) displays the result. By their relative position, you can see which color is replaced by which. It's time to turn to the scales. By changing the position of the slider under the color tone, we shift the entire color tone of the image. Reds, for example, become blue, yellows become blue, greens become crimson, blues become red, and so on. The second scale (saturation) is responsible for the amount of color. The extreme left position will make our photo "black and white". The right will bring the brightness of the colors to extremely high levels. The third is the light level. Move the slider to the left to create a black rectangle. To the right is white. The closest analogue is the Levels tool sliders. The advantage of using the hue / saturation tool (especially working with tone only) is the complete preservation of the balance of colors in the image. And, of course, brightness, contrast, saturation. There is one exception. Gray in HSB and HSL models is on the center axis. And changing the color tone does not in any way affect its shades. Take a look at the picture below. By moving the color tone slider, we changed the color of the sky above the "house with chimeras". The color of the highlights on the tinted glass of the dome on the right has also changed. BUT the color of the walls remained almost the same.
Now let's turn to a familiar photo of a forest lake.
The main tone that is present in the image is shades of yellow. Accordingly, replacing yellow with another color can drastically change the look of a photo. The algorithm of actions is as follows:
The result is in the illustration below.
If you have the time and desire, you can refine some areas with a soft eraser. For example, erase the sand, water and sky zones on the top layer. This will return the earth, lake and clouds to their natural shade. How to do this is described in detail in the previous lesson. After basic adjustments, set the desired blend modes of the layer and transparency. The result is much more natural than what you get with the Color Balance or Levels tools. This is enough to make " Hue / Saturation " part of your arsenal of mechanisms for changing the color of an image. Practical advice
For the rest - effective compositions and success in changing colors. The Topic of Article: Lessons Photoshop. Topic 4. Color correction. Lesson 3. Change color with the Hue / Saturation tool. |
Before we get started, it's worth talking a little about how color is represented in a computer. That is, about the variety of color spaces. We have already described the main ones in the lessons "selection by color" and "sharpening with channels." Spaces RGB, CMYK LAB are familiar. Don't repeat yourself.
