Photoshop cs5 by steve Johnson part 30 pps

ptg Chapter 8 Understanding Colors and Channels 187 The Duotone Color mode converts a grayscale image into a monotone (1-color), duotone (2-color), tritone (3-color), or quadtone (4-color) image using 1 to 4 custom inks. Duotones are frequently used to increase the tonal depth of a grayscale image. For example, most print- ing presses produce 50 levels of gray per color. By converting an image into a duotone, and using black and a mid-gray value, the press can produce a grayscale image with more dynamic range. A more common method for employing the Duotone color mode is to create an image with an overall color cast, for example, by converting the grays in the image to a sepia tone. If you're uncertain how to create the proper color mix for a duotone image, Photoshop comes equipped with dozens of sample duotone, tritone, and quadtone color presets. Understanding the Duotone Color Mode Convert an Image to Duotone Open an image. Click the Image menu, point to Mode, and then click Duotone. IMPORTANT Before converting an image into a duotone, it must first be in the Grayscale color mode. Choose from duotone presets available in the Preset drop-down menu. Choose to save or load a preset by clicking on the menu options triangle to the right of the preset menu. Click the Type list arrow, and then select from the following options: ◆ Monotone. Uses one color to generate image tone (limited dynamic range). ◆ Duotone. Uses two colors to generate image tone (better dynamic range for B&W images). ◆ Tritone. Uses three colors to generate image tone. ◆ Quadtone. Uses four colors to generate image tone. Click the Overprint Colors button to adjust how the colors will display when the inks are printed. Click OK. 5 4 3 2 1 3 1 5 Duotone color mode 2 4 From the Library of Wow! eBook ptg 188 Chapter 8 The Multichannel color mode is a specialized mode that converts the original color channels into shades of gray, with the grays based on the luminosity values of the original image. The original channels are con- verted into spot colors. Since Multichannel mode is used almost exclu- sively by the printing industry, converting a CMYK image into Multichannel color mode produces Cyan, Magenta, Yellow, and Black spot channels, and converting an RGB image into Multichannel mode produces Cyan, Magenta, and Yellow spot channels, minus the Black channel. In both instances, converting to Multichannel Color mode causes the loss of the Composite channel. Using Multichannel Color Mode Use the Multichannel Color Mode Open an image. Click the Image menu, point to Mode, and then click Multichannel. Photoshop converts the image into the Multichannel mode. IMPORTANT Images converted to the Multichannel mode must be saved in the DCS 2.0 format (Desktop Color Separations). The DCS 2.0 format generates a separate file for each of the image’s spot colors. 2 1 1 The Multichannel panel minus the Composite channel See Also See “Preparing an Image for the Press” on page 402 for more informa- tion on saving an image in the DCS 2.0 format. From the Library of Wow! eBook ptg Chapter 8 Understanding Colors and Channels 189 Photoshop's Replace Color command lets you create a selection based on image color, and replace that color selection with any other color. The Replace Color adjustment accomplishes this by giving you access to the three components of color: Hue, Saturation, and Brightness. Hue gives you the ability to change the image's actual color, Saturation con- trols the amount of color, and Brightness determines how bright the color is based on its Hue and Saturation. Using the Replace Color Adjustment Use the Replace Color Adjustment Open a color document. Click the Image menu, point to Adjustments, and then click Replace Color. Select the Localized Color Clusters check box if you want to limit your color selection to a specific area on the active document, using the Selection eyedroppers to select, add, or subtract colors. Click the Color box to select a specific color for the selection. Drag the Fuzziness slider to increase or decrease the sensitivity of the eyedropper tools. Click the Selection or Image option to toggle between a view of the selection mask and the active image (white areas of the mask represent selected areas). Drag the Hue, Saturation, and Lightness sliders to change the selected areas. Select the Preview check box to view the changes in the active document. Click OK. 9 8 7 6 5 4 3 2 1 3 4 8 6 7 9 5 From the Library of Wow! eBook ptg 190 Chapter 8 Photoshop not only lets you select virtually any colors you desire, it also lets you store those colors for future use. For example, you create a color scheme for a recurring brochure and you want a way to save those colors, or you're working on an Internet graphic and you need a web-safe color panel. Whatever your color needs, Photoshop stands ready to meet them. The Color panel gives you access to Photoshop's color-generation tools. This single panel lets you create colors using 6 different sliders, 2 spectrum color selectors, a grayscale ramp, and an option that lets you create a color ramp for the current foreground and background colors. Working with the Color Panel Work with the Color Panel Select the Color panel. Click the Color Options button. Select from the following Color Sliders: ◆ Grayscale. Creates a single slider going from white (0) to black (100). ◆ RGB. Creates three sliders (red, green, and blue). Each slider has a possible value from 0 to 255. ◆ HSB. Creates three additive sliders (hue, saturation, and brightness). Each slider has a possible value from 0 to 255. ◆ CMYK. Creates four subtractive sliders (cyan, magenta, yellow, and black). Each slider has a possible value from 0 to 100. ◆ Lab. Creates three sliders (L, a, and b). The L slider has a possible value from 0 to 120, and the a, b sliders have a possible value from -120 to 100. ◆ Web Color. Creates three sliders (red, green, and blue). Each slider has a possible hexadecimal value from 00 to FF. 3 2 1 1 2 3 From the Library of Wow! eBook ptg Chapter 8 Understanding Colors and Channels 191 Click the Color Options button, and then select from the following Spectrums or Ramps: ◆ RGB. Converts the lower portion of the Color panel to the RGB spectrum. Clicking anywhere in the spectrum changes the active color. ◆ CMYK. Converts the lower portion of the Color panel to the CMYK spectrum. Clicking anywhere in the spectrum changes the active color. ◆ Grayscale. Converts the lower portion of the Color panel to a grayscale ramp. Clicking anywhere in the ramp changes the active color. ◆ Current Colors. Converts the lower portion of the Color panel to a color ramp, using the current foreground and background colors. Clicking anywhere in the ramp changes the active color. To re stri ct the color ra mp to only web-safe colors, click the Color Options button, and then click Make Ramp Web Safe. To ch ange a col or using the Ad obe Color Picker, double-click a color box, select a color using the color range or color mode options, and then click OK. You can choose colors using four color models: HSB, RGB, Lab, and CMYK. 6 5 4 5 4 6 Select options or click the color range to select a color. Cube indicates the color is not web-safe; click to select the closest web color. An alert triangle indicates the color is out of gamut (non-printable). Understanding Spectrums and Ramps Spectrums and Ramps are located at the bottom of the Color panel, and represent the entire spectrum for the chosen color space. For example, the CMYK spectrum displays a rainbow of colors in the CMYK color gamut. Moving the eyedropper into the spectrum box and clicking lets you select any color and gives you a visual repre- sentation of the relationships between various colors. The Grayscale Ramp gives you linear access to the 256 available grayscale values. For Your Information From the Library of Wow! eBook ptg 192 Chapter 8 Photoshop not only lets you select virtually any colors you desire, it also lets you store those colors for future use in a library of color swatches, the Swatches Panel. Where the Color panel lets you select virtually any color you need, the Swatches panel lets you save and use specific colors that you use often. By default, the Swatches panel holds over 30 predefined color swatches, and has the ability to save as many user-defined swatches as you desire. Working with the Swatches Panel Add a Color Swatch to the Swatches Panel Select the Swatches panel. Click the Swatches Options button, and then choose from the predefined color swatches. Click the Append button to add the selected color swatch to the panel. Change and Delete Colors on the Swatches Panel Select the Swatches panel. Select a color, and then change the following: ◆ Foreground. Change the color by clicking on any color in the Swatches panel. ◆ Background. Change the color by holding down the Ctrl (Win) or A (Mac) key, and then clicking on any color in the Swatches panel. ◆ Delete. Hold down the Alt (Win) or Option (Mac) key (your cursor will turn into a pair of scissors), and then click the color in the Swatches panel. 2 1 3 2 1 2 2 1 1 From the Library of Wow! eBook ptg Chapter 8 Understanding Colors and Channels 193 Add Colors to the Swatches Panel Select the Color panel, and then drag the sliders or enter values to create a new color swatch. Select the Swatches panel, and then drag the lower right corner to expand its size beyond the range of the available colors. Move the cursor just below the last swatch color until it resembles a paint bucket. Click once, name the color, and then click OK. Save Customized Swatch Panels Select the Swatches panel. Create a customized swatch panel by adding and/or deleting colors from an existing panel. Click the Swatches Options button, and then click Save Swatches. Enter a name in the Save As box. Click the Save In (Win) or Where (Mac) list arrow, and then select a location to store the swatch. Click Save. 6 5 4 3 2 1 4 3 2 1 3 4 2 3 1 6 1 5 Did You Know? You can access your customized swatches from the Swatches Options button. When you save swatches in the Color Swatches folder (default loca- tion), your customized swatches appear at the bottom of the Swatches Options menu. From the Library of Wow! eBook . overall color cast, for example, by converting the grays in the image to a sepia tone. If you're uncertain how to create the proper color mix for a duotone image, Photoshop comes equipped with. you need a web-safe color panel. Whatever your color needs, Photoshop stands ready to meet them. The Color panel gives you access to Photoshop& apos;s color-generation tools. This single panel. Swatches panel lets you save and use specific colors that you use often. By default, the Swatches panel holds over 30 predefined color swatches, and has the ability to save as many user-defined