About foreground and background colors
Photoshop uses the foreground color to paint, fill, and stroke selections and the background color to make gradient fills and fill in the erased areas of an image. The foreground and background colors are also used by some special effects filters.
You can designate a new foreground or background color using the Eyedropper tool, the Color panel, the Swatches panel, or the Adobe Color Picker.
The default foreground color is black, and the default background color is white. (In an alpha channel, the default foreground is white, and the background is black.)
The current foreground color appears in the upper color selection box in the toolbox; the current background color appears in the lower box.
Foreground and background color boxes in toolbox
- To change the foreground color, click the upper color selection box in the toolbox, and then choose a color in the Adobe Color Picker.
- To change the background color, click the lower color selection box in the toolbox, and then choose a color in the Adobe Color Picker.
- To reverse the foreground and background colors, click the Switch Colors icon in the toolbox.
- To restore the default foreground and background colors, click the Default Colors icon in the toolbox.
The Eyedropper tool samples color to designate a new foreground or background color. You can sample from the active image or from anywhere else on the screen.
- In the options bar, change the sample size of the eyedropper by choosing an option from the Sample Size menu:3 by 3 Average, 5 by 5 Average, 11 by 11 Average, 31 by 31 Average, 51 by 51 Average, 101 by 101 AverageReads the average value of the specified number of pixels within the area you click.
Selecting a foreground color with the Eyedropper tool - To select a new foreground color, click in the image. Alternatively, position the pointer over the image, press the mouse button, and drag anywhere on the screen. The foreground color selection box changes dynamically as you drag. Release the mouse button to pick the new color.
- To select a new background color, Alt-click (Windows) or Option-click (Mac OS) in the image. Alternatively, position the pointer over the image, press Alt (Windows) or Options (Mac OS), press the mouse button, and drag anywhere on the screen. The background color selection box changes dynamically as you drag. Release the mouse button to pick the new color.
Note:To use the Eyedropper tool temporarily to select a foreground color while using any painting tool, hold down Alt (Windows) or Option (Mac OS).
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In the Adobe Color Picker, you choose colors using four color models: HSB, RGB, Lab, and CMYK. Use the Adobe Color Picker to set the foreground color, background color, and text color. You can also set target colors for different tools, commands, and options.
You can configure the Adobe Color Picker to let you choose only colors that are part of the web-safe palette or choose from specific color systems. You can also access an HDR (high dynamic range) picker to choose colors for use in HDR images.
The Color field in the Adobe Color Picker displays color components in HSB color mode, RGB color mode, and Lab color mode. If you know the numeric value of the color you want, you can enter it into the text fields. You can also use the color slider and the color field to preview a color to choose. As you adjust the color using the color field and color slider, the numeric values are adjusted accordingly. The color box to the right of the color slider displays the adjusted color in the top section and the original color in the bottom section. Alerts appear if the color is not a web-safe color 
or is out of gamut for printing (non-printable) 
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or is out of gamut for printing (non-printable) .
Adobe Color Picker
Note:
When you select a color in the Adobe Color Picker, it simultaneously displays the numeric values for HSB, RGB, Lab, CMYK, and hexadecimal numbers. This is useful for viewing how the different color models describe a color.
Although Photoshop uses the Adobe Color Picker by default, you can use a different color picker than the Adobe Color Picker by setting a preference. For example, you can use the built-in color picker of your computer’s operating system or a third-party plug-in color picker.
- In the toolbox, click the foreground or background color selection box.
- In the Color panel, click the Set Foreground Color or Set Background Color selection box.The Color Picker is also available when features let you choose a color. For example, by clicking the color swatch in the options bar for some tools, or the eyedroppers in some color adjustment dialog boxes.
You can choose a color by entering color component values in HSB, RGB, and Lab text boxes, or by using the color slider and the color field.
To choose a color with the color slider and color field, click in the color slider or move the color slider triangle to set one color component. Then move the circular marker or click in the color field. This sets the other two color components.
As you adjust the color using the color field and color slider, the numeric values for the different color models adjust accordingly. The rectangle to the right of the color slider displays the new color in the top half and the original color in the bottom. Alerts appear if the color is not a web-safe color or is out of gamut .
or is out of gamut .
Note:
You can choose a color outside the Adobe Color Picker window. Moving the pointer over the document window changes it to the Eyedropper tool. You can then select a color by clicking in the image. The selected color is displayed in the Adobe Color Picker. You can move the Eyedropper tool anywhere on your desktop by clicking in the image and then holding down the mouse button. You can select a color by releasing the mouse button.
Using the HSB color model, the hue is specified in the color field, as an angle from 0° to 360° that corresponds to a location on the color wheel. Saturation and brightness are specified as percentages. In the color field, the hue saturation increases from left to right and the brightness increases from the bottom to top.
When choosing a color based on the Lab color model, the L value specifies the luminance of a color. The A value specifies how red or green a color is. The B value specifies how blue or yellow a color is.
You can choose a color by specifying each component value as a percentage of cyan, magenta, yellow, and black.
You can choose a color by specifying a hexadecimal value that defines the R, G, and B components in a color. The three pairs of numbers are expressed in values from 00 (minimum luminance) to ff (maximum luminance). For example, 000000 is black, ffffff is white, and ff0000 is red.
The heads-up-display (HUD) color picker lets you quickly choose colors while painting in the document window, where image colors provide helpful context.
Note:
The HUD color picker requires OpenGL. (See Enable OpenGL and optimize GPU settings.)
Choosing color with HUD picker
Note:
To instead select a color from the image, hold down Alt (Windows) or Option (Mac OS) to access the Eyedropper tool.
The web‑safe colors are the 216 colors used by browsers regardless of the platform. The browser changes all colors in the image to these colors when displaying the image on an 8‑bit screen. The 216 colors are a subset of the Mac OS 8‑bit color palettes. By working only with these colors, you can be sure that art you prepare for the web will not dither on a system set to display 256 colors.
If you select a non‑web color, an alert cube appears next to the color rectangle in the Adobe Color Picker.
appears next to the color rectangle in the Adobe Color Picker.- Choose Make Ramp Web Safe from the Color panel menu. Any color you pick with this option selected is web‑safe.
- Choose Web Color Sliders from the Color panel menu. By default, web color sliders snap to web‑safe colors (indicated by tick marks) when you drag them. To override web‑safe color selection, Alt-drag (Windows) or Option-drag (Mac OS) the sliders.
Some colors in the RGB, HSB, and Lab color models cannot be printed because they are out-of-gamut and have no equivalents in the CMYK model. When you choose a non-printable color in either the Adobe Color Picker or the Color panel, a warning alert triangle appears. A swatch below the triangle displays the closest CMYK equivalent.
Note:
In the Color panel, the alert triangle is not available if you are using Web Color Sliders.
The Adobe Color Picker lets you choose colors from the PANTONE MATCHING SYSTEM®, the Trumatch® Swatching System™, the Focoltone® Colour System, the Toyo Color Finder™ 1050 system, the ANPA-Color™ system, the HKS® color system, and the DIC Color Guide.
To ensure that the final printed output is the color you want, consult your printer or service bureau and choose your color based on a printed color swatch. Manufacturers recommend that you get a new swatch book each year to compensate for fading inks and other damage.
Note:
Photoshop prints spot colors to CMYK (process color) plates in every image mode except Duotone. To print true spot color plates, create spot color channels.
ANPA-COLOR
Commonly used for newspaper applications. The ANPA-COLOR ROP Newspaper Color Ink Book contains samples of the ANPA colors.
DIC Color Guide
Commonly used for printing projects in Japan. For more information, contact Dainippon Ink & Chemicals, Inc., in Tokyo, Japan.
FOCOLTONE
Consists of 763 CMYK colors. Focoltone colors help avoid prepress trapping and registration problems by showing the overprints that make up the colors. A swatch book with specifications for process and spot colors, overprint charts, and a chip book for marking up layouts are available from Focoltone. For more information, contact Focoltone International, Ltd., in Stafford, United Kingdom.
HKS swatches
Used for printing projects in Europe. Each color has a specified CMYK equivalent. You can select from HKS E (for continuous stationery), HKS K (for gloss art paper), HKS N (for natural paper), and HKS Z (for newsprint). Color samplers for each scale are available. HKS Process books and swatches have been added to the color system menu.
PANTONE®
Colors used for spot-color reproduction. The PANTONE MATCHING SYSTEM can render 1,114 colors. PANTONE color guides and chip books are printed on coated, uncoated, and matte paper stocks to ensure accurate visualization of the printed result and better on-press control. You can print a solid PANTONE color in CMYK. To compare a solid PANTONE color to its closest process color match, use the PANTONE solid to process guide. The CMYK screen tint percentages are printed under each color. For more information, contact Pantone, Inc., Carlstadt, NJ (www.pantone.com).
TOYO Color Finder 1050
Consists of more than 1,000 colors based on the most common printing inks used in Japan. TheTOYO Process Color Finder book and swatches have been added to the color system menu. The TOYO Color Finder 1050 Book contains printed samples of Toyo colors and is available from printers and graphic arts supply stores. For more information, contact Toyo Ink Manufacturing Co., Ltd., in Tokyo, Japan.
TRUMATCH
Provides predictable CMYK color matching with more than 2,000 achievable, computer-generated colors. Trumatch colors cover the visible spectrum of the CMYK gamut in even steps. The Trumatch Color displays up to 40 tints and shades of each hue, each originally created in four-color process and each reproducible in four colors on electronic imagesetters. In addition, four-color grays using different hues are included. For more information, contact Trumatch Inc., in New York City, New York.
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