Adobe photoshop cc on demand 12

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Understanding Colors and Channels Introduction In the world of design, color is one of the most important ele- ments. When you're creating a brochure, advertisement, or banner using Adobe Photoshop, good use of color attracts the attention of the viewer. It also helps draw the elements of your design into one cohesive unit. Color is a strong motiva- tor and is used in all aspects of our daily life. Since color is so important to design, Photoshop lets you use industry-standard color sets, or you can create and save your own customized color panels. You can also color-correct a photograph by removing the color entirely or selectively removing colors from portions of the image. In addition, Photoshop gives you ways to select areas based on color, and then fill those areas with any color you choose. Not only is it important to understand how color is used, it's also important to understand how Photoshop manages color information and that's where the Channels panel comes into the picture. Channels are where color information is stored. The number of channels in an image is based on its color mode, or color model, such as RGB (Red, Green, and Blue) or CMYK (Cyan, Magenta, Yellow, and Black). A firm understanding of channels and color modes, and their func- tion in Photoshop, will go a long way in helping you control and manage color. When adjusting your image, you can use various com- mands-Auto Contrast and Color, Curves, Color Balance, Brightness/Contrast, and Desaturate, just to name a few. You can also use the Match Color and Selective Color adjust- ments to further fine-tune your image. Photoshop also pro- vides a Photo Filter adjustment, as well as a Shadows and Highlights adjustment to correct those overexposed or under- exposed images. With all of the commands and adjustments available, the real dilemma will be, where do you begin? / What You'll Do Work with 8-, 16-, and 32-Bit Images Work with the Channels Panel Work with Color Modes Understand the Various Color Modes Use the Replace Color Adjustment Work with the Color Panel Work with the Swatches Panel Use the Stroke and Fill Commands Create Spot Color Channels Use Auto Contrast and Auto Color Use Levels Adjustment Commands Use the Exposure Adjustment Use Curves and Color Adjustments Use Hue, Saturation, and Vibrance Use Match and Selective Color Use Channel Mixer and Gradient Map Use Photo Filter and Shadows/Highlights Use the Invert and Equalize Commands Use the Threshold and Posterize Adjustments Use the HDR Toning Adjustment Use the Black & White Adjustment 191

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Transcript of Adobe photoshop cc on demand 12

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Understanding Colors andChannels

Introduction

In the world of design, color is one of the most important ele-ments. When you're creating a brochure, advertisement, orbanner using Adobe Photoshop, good use of color attractsthe attention of the viewer. It also helps draw the elements ofyour design into one cohesive unit. Color is a strong motiva-tor and is used in all aspects of our daily life.

Since color is so important to design, Photoshop lets youuse industry-standard color sets, or you can create and saveyour own customized color panels. You can also color-correcta photograph by removing the color entirely or selectivelyremoving colors from portions of the image. In addition,Photoshop gives you ways to select areas based on color,and then fill those areas with any color you choose.

Not only is it important to understand how color is used,it's also important to understand how Photoshop managescolor information and that's where the Channels panel comesinto the picture. Channels are where color information isstored. The number of channels in an image is based on itscolor mode, or color model, such as RGB (Red, Green, andBlue) or CMYK (Cyan, Magenta, Yellow, and Black). A firmunderstanding of channels and color modes, and their func-tion in Photoshop, will go a long way in helping you controland manage color.

When adjusting your image, you can use various com-mands-Auto Contrast and Color, Curves, Color Balance,Brightness/Contrast, and Desaturate, just to name a few. Youcan also use the Match Color and Selective Color adjust-ments to further fine-tune your image. Photoshop also pro-vides a Photo Filter adjustment, as well as a Shadows andHighlights adjustment to correct those overexposed or under-exposed images. With all of the commands and adjustmentsavailable, the real dilemma will be, where do you begin?

/

What You'll Do

Work with 8-, 16-, and 32-Bit Images

Work with the Channels Panel

Work with Color Modes

Understand the Various Color Modes

Use the Replace Color Adjustment

Work with the Color Panel

Work with the Swatches Panel

Use the Stroke and Fill Commands

Create Spot Color Channels

Use Auto Contrast and Auto Color

Use Levels Adjustment Commands

Use the Exposure Adjustment

Use Curves and Color Adjustments

Use Hue, Saturation, and Vibrance

Use Match and Selective Color

Use Channel Mixer and Gradient Map

Use Photo Filter and Shadows/Highlights

Use the Invert and Equalize Commands

Use the Threshold and PosterizeAdjustments

Use the HDR Toning Adjustment

Use the Black & White Adjustment

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Working with 8-, 16-, and 32-Bit Images

It's all about the numbers, and that's a fact.The number of colors available for displayingor printing each pixel in an image is called bitdepth-also known as pixel depth or colordepth. A higher bit depth means more avail-able colors and more accurate color represen-tation in an image. A bit depth setting of 2bits displays 4 colors, 4 bits displays 16 col-ors, 8 bits displays 256 colors, 16 bits displays32,768 colors, and 24 bits and 32 bits bothdisplay 16.7 million colors. Most digitalimages currently use 8 bits of data per chan-nel. For example, an RGB image with 8 bitsper channel is capable of producing 16.7 mil-lion (a 24-bit RGB image: 8 bits x 3 channels)possible colors per pixel. While that mayseem like a lot of color information, when itcomes to color correction and adjustment, itisn't.

In response to Photoshop users needingmore control, Photoshop supports 16-bit andnow 32-bit-known as High Dynamic Range

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When you correct a 8-bit image. it can lose tonal values.

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(HDR)-images. High Dynamic Range imageswith 32 bits per channel have a moreextended dynamic range than lower bit depthimages. Dynamic Range describes the abilityof a channel to capture maximum informationfrom the black to white and dark and brightareas of an image. An 8-bit channel image hasa dynamic range of 250:1 (per channel), simi-lar to the dynamic range of printed paper or acomputer display. A 16-bit channel image hasa dynamic range of 65,000:1, and a 32-bitchannel image has a dynamic range of over200,000:1.The greater dynamic range trans-lates into better control over an image whenmaking fine color and contrast adjustmentsusing Levels and Curves (shown below).Working with HDR images is very similar tousing raw files and applying exposurechanges after the fact. Photographers cancapture the full dynamic range of a scenewith multiple exposures and merge the filesinto a single image.

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16- and 32-bit images hold more image data and thereforeprovide more to work with during correction operations.

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C ann ••ln B"t e Ch nnThe ability to work with 32-bit images is rela-tively new in Photoshop, and initially you hada limited use of adjustments and filters.However, in Photoshop many more adjust-ments and filters have become available for32-bit images, such as Hue/Saturation, Levels,Gaussian Blur, Add Noise, Smart Sharpen,Channel Mixer, and more.

When adjusting the color or contrast of animage, first convert a standard 8-bit image to16 bits, and then make your corrections. Thishelps prevent loss of color information, andbanding between light and dark shades. Onceall the color/contrast adjustments have beenmade, you can (if necessary) convert theimage back to 8 bits. It's that simple. You canchange an image's bit depth by displaying theimage, clicking the Image menu, pointing toMode, and then clicking 8 Bits/Channel, 16Bits/Channel, or 32 Bits/Channel.

When you convert a 32-bit image to 8 or16 bits per channel, if you choose to mergeyour layers before changing the bit depth,Photoshop opens the HDRToning dialog boxto let you make exposure and contrast correc-tions so the image retains the dynamic rangeyou want. The Exposure and Gamma optionlets you manually adjust brightness and con-trast. Drag the Exposure slider to adjust thegain and drag the Gamma slider to adjust thecontrast. The Highlight Compression option

automatically adjusts highlight values to fitwithin the range for 8- or 16-bit images. TheEqualize Histogram option automatically pre-serves image contrast. The Local Adaptationoption adjusts the tonality (local brightnessregions) in the image. Drag the Radius sliderto specify the size of the local brightnessregions and then drag the Threshold slider tospecify the distance between tonal valuesbefore they are included in the brightnessregion. If you want to reuse these settings inthe future, you can save them, and then loadthem again as needed.

Viewi 9 32- it Im 9The dynamic range of HDR images exceedsthe display capabilities of standard monitors.When you view a 32-bit HDR image, the high-lights and shadows may look dark or washedout. To correct the problem, Photoshop allowsyou to adjust 32-bit preview options so 32-bitimages display properly on your monitor. Thepreview options are stored in the image file,so each file retains its own settings. To set pre-view options, open a 32-bit HDR image, clickthe View menu, and then click 32-Bit PreviewOptions. In the 32-bit Preview Options dialogbox, select the preview settings you want(described earlier in this topic), and then clickOK.

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Work with the Channels Panel

0 Open a color document.

0 Select the Channels panel. .5Eo Click on the individual channels to <RI X2view the native color channels ofthe active document. <RI X3

• Click the composite channel to <RI X4view the full-color image.

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Working with theChannels Panel

See AlsoSee "Creating Spot Color Channels" onpage 212 for more information on usingthe Channels panel.See "Using Channels to Create andStore Selections" on page 100for moreinformation on using channels.

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The Channels panel is Photoshop's storage locker for color and selec-tion information. For example, when you open an RGB image, theChannels panel displays color channels of red, green, and blue. Whenyou open a CMYK image, the color channels are cyan, magenta, yellow,and black. These primary color channels are defined as the nativecolor channels of the image. The Channels panel can also contain spotcolor channels and selection masks. In addition to color informationand selection masks, the Channels panel contains a composite chan-nel. The composite, when selected, lets you view the full-calor image inthe document window. Selecting any of the individual native colorchannels changes the active view of the image to display the selectedcolor channel. The Channels panel stores color information usingshades of gray, and each color channel is capable of displaying 256gradations from black to white. A zero-value pixel displays as black,and a 255-value pixel displays as white. The darker the shade of gray,the less of the selected ink color is used to create the visible colorswithin the image.

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Working with Color Modes

Color modes define the colors represented inthe active document. Although you canchange the color mode of a document, it isbest to select the correct color mode at thestart of the project. Photoshop's color modesare Bitmap, Grayscale, Duotone, IndexedColor, RGB (Red, Green, and Blue), CMYK(Cyan, Magenta, Yellow, and Black), Lab, andMultichannel. See "Selecting Color Modes andResolution" on page 13 for information on thebest use for each color mode. The number ofchannels in an image depends on its colormode. For example, a CMYK image containsat least four channels, one for each color.

Color modes determine the number of col-ors, the number of channels, and the file sizeof an image. For example, an RGB image hasat least three channels (like a printing plate),one for red, green, and blue color information.Color modes not only define the workingcolor space of the active document, they alsorepresent the color space of the output docu-ment. It's the document output (print, press,or monitor) that ultimately determines thedocument color mode. Color modes do notjust determine what colors the eye sees; theyrepresent how the colors are mixed, andthat's very important because different outputdevices use different color mixes.

Therefore, when selecting a color mode,know the file format of the document andwhere it will be used. An image taken with adigital camera and then opened in Photoshopwould most likely be in the RGB color mode.An image displayed on a monitor would beRGB, or possibly Indexed Color. A photographscanned on a high-end drum scanner wouldmost likely be in the CMYK color mode. Animage being sent to a 4-color press would beCMYK, too. If you were creating a Photoshop

document from scratch, the color modeyou choose should represent the eventualoutput destination of the document, suchas on a web page, to an inkjet printer, or a4-color press.

Switchinq Between Color ModesUnfortunately, images do not always arrivein the correct format. For example, youtake several photographs with your digital(RGB) camera, but the images are beingprinted on a 4-color (CMYK) press, or youwant to colorize a grayscale image.Changing color modes is a snap, butchanging the color mode of an image isn'tthe problem. The problem is what happensto the digital color information when youchange color modes. For example, if youopen an RGB image with the intent ofsending it out to a 4-color press (CMYK),the smartest course of action is to remainin the RGB color mode through the pro-cessing of the image, and then convert theimage into the CMYK mode at the end.Thereason has to do with how Photoshopmoves between those two color spaces.For example, if you move a color-correctedCMYK image into the RGBcolor mode,and then back to CMYK, the colors shiftbecause Photoshop rounds color valuesduring the change process. On top of that,a CMYK image is 25% larger than an RGBimage, and the RGB color mode repre-sents the color space of your monitor, nota printing press. It is impossible to viewsubtractive CMYK color on an RGBdevice.If, however, the image originally came toyou as a color-corrected CMYK image,then stay in and work inside that colormode.

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Understanding theRGB Color Mode

Convert an Image to RGB Color

o Open an image.

o Click the Image menu, point toMode, and then click RGB Color.

Photoshop converts the imageinto the RGB color mode.

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The RGB color mode is probably the most widely used of all the colormodes. RGB generates color using three 8-bit channels: 1 red, 1 green,and 1 blue. Since each channel is capable of generating 256 steps ofcolor, mathematically, that translates into 16)77,216 possible colors perimage pixel. The RGB color mode (sometimes referred to as AdditiveRGB) is the color space of computer monitors, televisions, and anyelectronic display. This also includes cell phones and mobile devices.RGB is considered a device-dependent color mode. Device-dependentmeans that the colors in images created in the RGB color mode willappear differently on various devices. In the world of computer moni-tors and the web, what you see is very seldom what someone elsesees; however, understanding how Photoshop manages color informa-tion goes a long way to gaining consistency over color.

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Understanding theCMYK Calor Mode

Convert an Image to CMYK Color

Open an image.

Click the Image menu, point toMode, and then click CMYK Color.

Photoshop converts the imageinto the CMYK color mode.

See AlsoSee "Using Curves and CalorAdjustments" on page 276 for moreinformation on adjusting the calor of animage.

The CMYK color mode is the color mode of paper and press. Printingpresses (sometimes referred to as a 4-color press) convert an image'scolors into percentages of CMYK (Cyan, Magenta, Yellow, and Black)'which eventually become the color plates on the press. One at a time,the plates apply color to a sheet of paper, and when all 4 colors havebeen applied, the paper contains an image similar to the CMYK imagecreated in Photoshop. The CMYK color mode can take an image from acomputer monitor to a printed document. Before converting an imageinto the CMYK mode, however, it's important to understand that youwill lose some color saturation during the conversion. The colors thatwill not print are defined as being out of gamut. To view the areas of anRGB image that will lose saturation values, click the View menu, andthen click Gamut Warning. Photoshop will mask all the areas of theimage that are out of gamut.

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Understanding theGrayscale Color Mode

Convert an Image to Grayscale

o Open an image .

• Click the Image menu, point toMode, and then click Grayscale.

The image is automaticallyconverted into the Grayscale colormode.

Did You Know?You can colorize a grayscale image.Convert the image into the RGBmode,and then select a color, brush, andbrush size on the Options bar. The trickis to change the blending mode of thebrush on the Options bar to Color.Then, as you paint on the image, theselected color will replace the originalgrays.

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The Grayscale color mode utilizes an 8-bit pixel (8 on/off light switches)to generate 1 black, 1 white, and 254 shades of gray. Although scanningand working on old black and white images might seem the obviousreason to use the Grayscale color mode, the speed and power ofPhotoshop, combined with faster computer systems, has promptedmost photo restorers to switch to the RGB color space because of itsgreater versatility and ability to generate millions of colors (or shadesof gray). Yet despite the move to RGB, the Grayscale color mode is stillused extensively with black and white images, where file size is a con-sideration (grayscale images are two-thirds smaller than RGB images),and when output to rag-style papers, such as newsprint, fail to producethe detailed information available with RGB.

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For Your Information

Colorizing a Grayscale ImageIf you're planning on colorizing a grayscale image, you can increaseyour control of the image by creating a layer directly above theimage layer, and painting in the new layer. Leavethe blending modeof the brush at Normal and change the blending mode of the newlayer to Color.When you paint, the color is applied and controlled inthe new layer, and you have the additional option of using layeropacity to control the intensity of the effect.

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Understanding theBitmap Calor Mode

Convert an Image to BitmapOpen an image.

Click the Image menu, point toMode, and then click Bitmap.

IMPORTANT Before convertingan image into a bitmap, it must firstbe in the Grayscale calor mode.

Enter a value for Output Resolution.

Click the Use list arrow, and thenselect from the available options:

50% Threshold. Converts pixelswith gray values above the middlegray level (128) to white andbelow to black. The result is ahigh-contrast, black-and-whiteimage.

Pattern Dither. Converts an imageby organizing the gray levels intogeometric patterns of black andwhite dots.

Diffusion Dither. Converts pixelswith gray values above the middlegray level (128)to white andbelow to black using an error-diffusion process. The result is agrainy, film-like texture.

Halftone Screen. Simulates theeffect of printing a grayscaleimage through a halftone screen.

Custom Pattern. Simulates theeffect of printing a grayscaleimage through a custom halftonescreen. This method lets youapply a screen texture, such as awood grain, to an image.

Click OK.

Bitmap images consist of two colors: black and white. Bitmap imagesare sometimes referred to as 1-bit images. Think of a bitmap as a lightswitch with two positions, on and off. Each pixel in a bitmap image iseither on or off, black or white. Because they are only 1 bit, the file sizeof a bitmap image is typically very small. Bitmap images have limiteduse, but often are employed for black and white ink drawings, line art,sketches, and for creating halftone screens.

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Understanding theIndexed Calor Mode

Convert an Image toIndexed Color

Open an image.

Click the Image menu, point toMode, and then click IndexedColor.

Select from the following IndexedColor Mode options:

• Palette. Click the list arrow tochoose from the available colorpanels, or click Custom andcreate your own palette.

Colors. Select the number ofcolors for the lookup table (3 to256).

• Forced. Force the lookup tableto hold specific colors. Blackand White adds a pure blackand a pure white to the colortable; Primaries adds red,green, blue, cyan, magenta,yellow, black, and white; webadds the 216 web-safe colors;and Custom allows you tospecify your own colors.

Transparency. Select the checkbox to preserve transparentareas of the image (if there areno transparent areas, thisoption is disabled).

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The Indexed Color mode gives you two advantages. You can createimages as small as grayscale (8-bit pixels). and you get color instead ofshades of gray. Its small file size and ability to generate color make it awinning color mode for images displayed on web pages, as well asgraphics used in computer-generated presentations. Its one drawbackis the number of colors generated; Indexed Color images generate amaximum of 256 colors (the same number as the steps of gray in agrayscale image). The good news is that you get to choose the colors.When you convert an image into the Indexed Color mode, Photoshopcreates a color lookup table (CLUT) to store the image's color informa-tion. When a color in the image cannot be found in the lookup table,Photoshop substitutes the closest available color.

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o Select from the following options:

Matte. Click the list arrow to filltransparent areas of theoriginal image with a specificcolor.

Dither. Click the list arrow, andthen select a pixel-mixing(dither) scheme. Dithering helpstransitional areas of the image(shadows, light to dark) appearmore natural.

• Amount. If the Dither option isselected, the Amount instructsPhotoshop how much colorinformation to use in thedithering process (1% to 100%).

Preserve Exact Colors. Selectthe check box to hold exactcolor measurements in thelookup table .

• Click OK.

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Understanding theLab Color Mode

Convert an Image to Lab Color

• Open an image .

• Click the Image menu, point toMode, and then click Lab Calor.

Photoshop converts the imageinto the Lab color mode.

Did You Know?You can use the Lab calor modeto archive RGB calor images.Since the Lab color space is device-independent, and RGBis device-dependent, archiving RGBimages inthe Lab color mode stabilizes theimage's color information and insurescolor accuracy, no matter what editingapplication is used.

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The Lab color mode is an old color measuring system. Created inFrance, its purpose was to measure color based on visual perception.Since personal computers had not been created at that time, the Labmode is not based on a particular computer or operating system, andso Lab color is device independent. The Lab mode measures colorusing a lightness channel, an "a" channel (red to green), and a "b" chan-nel (blue to yellow). Lab Color works well for editing images obtainedfrom Stock Photos, moving images between operating systems(Photoshop Mac to Photoshop Win), and for printing color images toPostScript Level 2 or 3 devices. Because of its ability to separate thegray tones of an image into an individual channel (lightness), the Labcolor mode is excellent for sharpening, or increasing the contrast of animage without changing its colors. Just convert the original RGB imageto Lab color, select the Lightness channel, and perform sharpening orLevels and Curves adjustments directly to the channel.

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Understanding theDuotone Color Mode

Convert an Image to Duotone

o Open an image. Click the Imagemenu, point to Mode, and thenclick Duotone.

IMPORTANT Before convertingan image into a duotone, it must bein the Grayscale calor mode.

To use a duotone preset, click thePreset list arrow, and then selectthe preset you want.

You can also save, load, ordelete a preset by clicking themenu options to the right of thepreset menu.o Click the Type list arrow, and then

select from the following options:

• Monotone. Uses one color togenerate image tone (limiteddynamic range).

Duotone. Uses two colors togenerate image tone (betterdynamic range for B&Wimages).

Tritone. Uses three colors togenerate image tone.

Ouadtone. Uses four colors togenerate image tone.

Click the Overprint Colors button toadjust how the colors will displaywhen the inks are printed.

Click OK.

The Duotone Color mode converts a grayscale image into a monotoneIt-color), duotone (2-color). tritone (3-color). or quadtone (4-color)image using 1 to 4 custom inks. Duotones are frequently used toincrease the tonal depth of a grayscale image. For example, most print-ing presses produce 50 levels of gray per color. By converting an imageinto a duotone, and using black and a mid-gray value, the press canproduce a grayscale image with more dynamic range. A more commonmethod for employing the Duotone color mode is to create an imagewith an overall color cast, for example, by converting the grays in theimage to a sepia tone. If you're uncertain how to create the propercolor mix for a duotone image, Photoshop comes equipped with dozensof sample duotone, tritone, and quadtone color presets.

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Chapter8 Understanding Colorsand Channels 203

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Using MultichannelCalor Mode

Use the MultichannelCalor Modeo Open an image.

Click the Image menu, point toMode, and then clickMultichannel.

Photoshop converts the imageinto the Multichannel mode.

IMPORTANT Imagesconverted to the Multichannelmode must be saved in the DCS2.0format (Desktop CalorSeparations). The DCS2.0 formatgenerates a separate file for eachof the images spot colors.

See AlsoSee "Preparing an Image for thePress" on page 438 for more informa-tion on saving an image in the DCS2.0format.

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The Multichannel color mode is a specialized mode that converts theoriginal color channels into shades of gray, with the grays based on theluminosity 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 intoMultichannel color mode produces Cyan, Magenta, Yellow, and Blackspot channels, and converting an RGB image into Multichannel modeproduces Cyan, Magenta, and Yellow spot channels, minus the Blackchannel. In both instances, converting to Multichannel Color modecauses the loss of the Composite channel.

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Using the ReplaceColor Adjustment

Photoshop's Replace Color command lets you create a selection basedon image color, and replace that color selection with any other color.The Replace Color adjustment accomplishes this by giving you accessto the three components of color: Hue, Saturation, and Brightness. Huegives you the ability to change the image's actual color, Saturation con-trols the amount of color, and Brightness determines how bright thecolor is based on its Hue and Saturation.

Use the Replace ColorAdjustment

Open a color document. eplace Col

Click the Image menu, point to OKAdjustments, and then click lusters

Replace Color. Cancel~t! Color:

Select the Localized Color Load...

Clusters check box if you want to 0Fuzziness: Save...limit your color selection to aspecific area on the activedocument, using the Selectioneyedroppers to select, add, orsubtract colors.

Click the Color box to select aspecific color for the selection.

Drag the Fuzziness slider to (0 Selection Olmage 1 0increase or decrease thesensitivity of the eyedropper tools. Replacement !IClick the Selection or Image Hue: Doption to toggle between a view ofthe selection mask and the active Saturation: Dimage (white areas of the mask 6represent selected areas). Lightness: D

0 Drag the Hue, Saturation, and 6Lightness sliders to change theselected areas.

Select the Preview check box toview the changes in the activedocument.

Click OK.

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Working with theColor Panel

Work with the Color Panel• Select the Color panel.

Click the Color Options button.o Select from the following CalorSliders:

Grayscale. Creates a singleslider going from white (0) toblack (100).

RGB. Creates three sliders (red,green, and blue). Each sliderhas a possible value from 0 to255.

HSB. Creates three additivesliders (hue, saturation, andbrightness). Each slider has apossible value from 0 to 255 .

• CMYK. Creates four subtractivesliders (cyan, magenta, yellow,and black). Each slider has apossible value from 0 to 100.

lab. Creates three sliders(L, a, and b). The L slider has apossible value from 0 to 100,and the a, b sliders have apossible value from -128 to 127.

Web Color. Creates threesliders (red, green, and blue).Each slider has a possiblehexadecimal value from 00to FF.

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Photoshop not only lets you select virtually any colors you desire, it alsolets you store those colors for future use. For example, you create acalor scheme for a recurring brochure and you want a way to savethose colors, or you're working on an Internet graphic and you need aweb-safe calor panel. Whatever your calor needs, Photoshop standsready to meet them. The Calor panel gives you access to Photoshop'scalor-generation tools. This single panel lets you create colors using 6different sliders, 2 spectrum calor selectors, a grayscale ramp, and anoption that lets you create a calor ramp for the current foreground andbackground colors. If you need more room to work in the Calor panel,you can resize it (New!).

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Click the Color Options button, andthen select from the followingSpectrums or Ramps:

RGB. Converts the lowerportion of the Col or panel to theRGB spectrum. Clickinganywhere in the spectrumchanges the active color.

CMYK. Converts the lowerportion of the Col or panel to theCMYK spectrum. Clickinganywhere in the spectrumchanges the active color.

Grayscale. Converts the lowerportion of the Color panel to agrayscale ramp. Clickinganywhere in the ramp changesthe active color.

Current Colors. Converts thelower portion of the Color panelto a color ramp, using thecurrent foreground andbackground colors. Clickinganywhere in the ramp changesthe active color.

To restrict the color ramp toonly web-safe colors, click theColor Options button, and thenclick Make Ramp Web Safe.

To change a color using the AdobeColor Picker, double-click a colorbox, select a color using the colorrange or color mode options, andthen click OK.

You can choose colors using fourcolor models: HSB, RGB, Lab, andCMYK.

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).

Color Picker (Fore round Col or)

OK

Cancel

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Select options or click the colorrange to select a color.

For Your Information

Understanding Spectrums and RampsSpectrums and Ramps are located at the bottom of the Color panel,and represent the entire spectrum for the chosen color space. Forexample, the CMYK spectrum displays a rainbow of colors in theCMYK color gamut. Moving the eyedropper into the spectrum boxand clicking lets you select any color and gives you a visual repre-sentation of the relationships between various colors. The GrayscaleRamp gives you linear access to the 256 available grayscale values.

Using Colors from the Kuler PanelThe Kuler panel is an extension in Photoshop that allows you to usegroups of color, or themes in your projects. You can use the panel tobrowse thousands of color themes, create your own using the com-plementary harmony rules, and share them with others in the Kulercommunity. After you find or create the theme you want, you canadd it to the Swatches panel for use in your project. Click theWindow menu, point to Extensions, and then click Kuler. Click theBrowse tab, search for or narrow down the browse list, select thetheme you want in the Kuler panel, and then click the Add SelectedTheme To Swatches button to add the selected theme to theSwatches panel.

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Working with theSwatches Panel

Add a Color Swatch to theSwatches Panel

Select the Swatches panel.

o Click the Swatches Optionsbutton, and then choose from thepredefined color swatches.

o Click the Append button to add theselected color swatch to thepanel.

Add Colors to the SwatchesPanel

o Select the Color panel, and thendrag the sliders or enter values tocreate a new color swatch.

o Select the Swatches panel.o Drag the lower right corner toexpand its size beyond the rangeof the available colors.o Move the cursor just below thelast swatch color until it resemblesa paint bucket.

• Click once, name the color, andthen click OK.

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Photoshop not only lets you select virtually any colors you desire, it alsolets you store those colors in the Swatches panel. Where the Colorpanel lets you select virtually any color you need, the Swatches panellets you save and use specific colors that you use often. By default, theSwatches panel holds over 100 predefined color swatches, and has theability to save as many user-defined swatches as you desire. You canalso load saved custom swatches (ACO) or ones from HTML, CSS, orSVG files (New!), web content. If a color on a swatch is not exactlywhat you want or you no longer need it, you can change or delete it.