Mixing with the Color palette in Photoshop

To open the Color palette, choose Window➪Color. A couple of swatches in this palette may look vaguely familiar. That’s because they represent the foreground and background colors, just like the swatches in the Toolbox. And just like the Toolbox swatches, if you click the swatches in the Color palette, the infamous Color Picker appears. But forget the Color Picker; you don’t need to go there. Everything you need is right here in this tiny palette. Before you use the Color Picker to define your colors, you should know which color model you want to use. Here is a short description of each:

-->RGB (Red-Green-Blue) is the color model used for anything that will be viewed onscreen from multimedia and slide presentations to content for the Web. Occasionally, you can use it if you plan to print using desktop inkjet printers.

-->CMYK (Cyan-Magenta-Yellow-Black) is the color model used in printing.

-->Web Color is the model used strictly for the Web. If you choose this model, make sure that you also choose Make Ramp Web Safe from the Color palette options menu.

-->HSB (Hue-Saturation-Brightness), is based on percentages of saturation and brightness and an angle (0 to 360 degrees), which corresponds to a location on the color wheel.

-->Lab (Lightness, a, b) color model contains three channels, one for lightness; one (a), which contains colors from green to red; and one (b), which contains colors from blue to red. Lab is more complex to understand and work with than the other models and is the color model of choice for high-end color experts. By the way, Lab is also Photoshop’s “native” color mode.

-->Grayscale is the color model if you want to work strictly in black and white and shades of gray. You’ll get one slider, K, which represents black. Move the slider to get shades of gray, including complete white and black.

Here are the quick and easy steps to define a color by using the Color palette:
1. Choose either the Foreground or Background color swatch in the Color palette.
You can change only one swatch at a time. If the one you want is already selected, do nothing. A double outline appears around the swatch indicating that it’s selected. If you accidentally click the swatch that is already selected, the Color Picker dialog box appears. Just click Cancel and start over.

2. Select your desired color model from the Color palette pop-up menu.
Your options are RGB Sliders, CMYK Sliders, Lab Sliders, Web Color Sliders, HSB Sliders, and Grayscale Slider. You’ll probably be using RGB, CMYK, or Web Color the majority of the time. If you’re not sure what these color models represent.

3. In the Color palette, move the sliders for each component of the color model or enter a numeric value.
RGB values are based on brightness levels, from 0 to 255, with 0 being black and 255 being the pure color or white. CMYK values are based on percentages (1–100) of the four process colors — Cyan, Magenta, Yellow, and Black. The Web Color model gives you only the 216 colors used by Web browsers.
You can also select a color by clicking inside the color ramp at the bottom of the Color palette. And to quickly return to the default colors, click the small black and white swatches at the end of the color ramp.

4. Keep an eye open for a triangular alert icon.
This icon is known as the gamut alarm. Its appearance is Photoshop’s way of saying, “Hey, you! That color you mixed won’t print like you think it will because it’s out of gamut.” Remember gamut is the range of colors a device can either display or print. Because the RGB color model has a much wider gamut than the CMYK color model, some of the colors can only be viewed on-screen and not reproduced on paper. Photoshop offers you a substitution. Inside a little square to the right of the
gamut alarm icon, the closest printable color to the one you chose appears.

5. Click either the icon or the square if you want to use the closest printable color rather than your original choice.
The gamut alarm isn’t applicable if you choose Web Color Sliders. You have another kind of alarm described next. If you want to use the RGB color model but also want to ensure that any color you choose is printable, select CMYK Spectrum from the Color palette options menu. By default, all the colors in the ramp are printable. Just be sure to choose your colors by clicking in the ramp.

6. Be on the lookout for a small cube icon. Click either the icon or the square to use the closest Web-safe color.
The cube indicates that the color you mixed is not a Web-safe color. Clicking the cube tells Photoshop that you want to use its Web-safe alternative instead. A Web-safe color ensures that the color will not dither (mixing available colors to simulate a missing color) when displayed in the browser.