ptg color management IN THIS CHAPTER Launching Photoshop . . . . . . . . . . . . 1 Displays, modes, and channels . . . . . . 2 Introduction to color management . . . 5 Setting a camera’s color space to Adobe RGB . . . . . . . . . . . . . . . . . 5 Calibrating your display . . . . . . . . . . . 7 Choosing a color space for Photoshop . . . . . . . . . . . . . . . . . 10 Synchronizing color settings . . . . . . 12 Customizing your color policies . . . . 13 Saving custom color settings . . . . . . 14 Acquiring printer profi les . . . . . . . . . 14 Changing color profi les . . . . . . . . . . 16 1 Welcome to Photoshop! In this chap- ter, you’ll launch the application and familiarize yourself with Photoshop color basics, such as displays, docu- ment color modes, and channels. Most important, before you start editing images — and also before outputting any les — you need to incor- porate color management into your workow. You’ll accomplish this by calibrating your display, choosing color settings, and downloading the necessary printer proles. Launching Photoshop To launch Photoshop in Windows: Do one of the following: In a 32-bit version of Windows, click the Start button on the taskbar, choose All Programs, then click Adobe Photoshop CS5. In a 64-bit version of Windows, click the Start button, choose All Programs, then click Adobe Photoshop CS5 (64-bit). Double-click a Photoshop le icon. To launch Photoshop in the Mac OS: Do one of the following: Click the Photoshop icon in the Dock. (If you haven’t created the icon yet, open the Adobe Photoshop CS5 folder in the Applications folder, then drag the Adobe Photoshop CS5 application icon into the Dock.) Open the Adobe Photoshop CS5 folder in the Applications folder, then double-click the Adobe Photoshop CS5 application icon. Double-click any Photoshop le icon. WANT TO SEE MORE ONSCREEN? If you want to open a fi le quickly to make the screen more “live” as you read through this chapter, navigate to the Samples folder inside the Photoshop applica- tion folder, then double-click a .psd image fi le, such as “Fish.psd.” (Don’t worry…you’ll soon learn how to open photos and create documents.) FINDING THE NEW STUFF This symbol ★ identifi es Photoshop features that are new or improved. ptg 2 Chapter 1 variables as the temperature of the display, the lighting in the room, and even the colors on your wall. Moreover, many colors that you see in the natural world or that can be displayed onscreen can’t be printed (have no ink equivalents), and conversely, some printable colors can’t be displayed onscreen. e color management techniques that we outline in this chapter will help smooth out the kinks in the color workow from digital input to display onscreen, then nally to print. ➤ In Photoshop, you can choose colors using the Grayscale, RGB (red-green-blue), HSB (hue- saturation-brightness), CMYK (cyan-magenta- yellow-black), or Lab (lightness, a-component, and b-component) color model, and you can choose colors from a color matching system, such as PANTONE. Photoshop channels All Photoshop images are composed of one, three, or four channels (see the sidebar below). In an RGB image, for example, the three channels store the intensity of red, green, or blue at each pixel as a level of gray. Most likely you will work with images that store 256 levels of gray for each chan- nel. Because the 256 gray levels are represented by 8 bits (short for “binary digits”) of computer data, the bit depth of such an image is said to be 8 bits per channel. Files that have a higher bit depth of 16 or 32 bits per channel contain more color infor- mation (see page 19). ➤ Open an RGB Color image and display the Channels panel. Click Red, Green, or Blue on the panel to display only that channel, then click the topmost channel name on the panel to restore the composite display. Although you Displays, modes, and channels Onscreen, your Photoshop image is a bitmap — a g e o m e t r i c a r r a n g e m e n t , o r m a p p i n g , o f d o t s o n a rectangular grid. Each dot, or pixel, represents a dierent color or shade. If you drag with a painting tool, such as the Brush, across an area of a layer, pixels below your pointer are recolored. With a high zoom level chosen for your document, you can see (and edit) individual pixels. A Bitmap programs like Photoshop are best suited for editing and pro- ducing photographic, painterly, or photorealistic images that contain subtle gradations of color, which are called “continuous tones.” e images you edit in Photoshop can originate from a digital camera, from a photo print that you have scanned, from a le saved in another application, or from scratch using program features, such as painting and cloning tools. To enable color images to be viewed onscreen, your display projects red, green, and blue (RGB) light. Combined in their purest form, these addi- tive primaries produce white light. If you were to send your Photoshop le to a commercial print shop for four-color process printing, it would be rendered with cyan (C), magenta (M), yellow (Y), and black (K) inks. Because computer displays use the RGB model, they can only simulate the CMYK inks that are used in commercial printing. e successful translation of a digital image to a printed one isn’t as simple as you might think. To begin with, the same document may look surpris- ingly dierent on dierent displays due to such A In this extreme close-up of a photo in Photoshop, you can see the individual pixels that the image is made of. DEFAULT NUMBER OF CHANNELS FOR EACH IMAGE MODE One Three Four Bitmap RGB CMYK Grayscale Lab Duotone Multichannel Multichannel Indexed Color ptg Color Management 3 can make adjustments to individual channels, normally you will edit all the channels at once while viewing the composite image. In addition to the core channels we just discussed, you can add two other types of channels. You can save a selection as a mask in a grayscale (alpha) channel, or add channels for individual spot colors. A e more channels a document contains, the larger its le storage size is. A document in RGB Color mode, which contains three channels (Red, Green, and Blue), will be three times larger than it would be if converted to Grayscale, a single- channel mode. If you were to convert it to CMYK Color mode, the le would contain four channels (Cyan, Magenta, Yellow, and Black) and would be larger still. Photoshop document color modes A document can be converted to, displayed in, and edited in any of these color modes: Bitmap, Grayscale, Duotone, Indexed Color, RGB Color, CMYK Color, Lab Color, or Multi channel. e ones you will work in the most are RGB Color and CMYK Color. To convert a document to a dierent mode, use the Image > Mode submenu. B If a mode is dimmed on the menu, it means you must convert B Use the Mode submenu to change the color mode of your document. Continued on the following page A An alpha channel A spot color channel Main image channels the le to a dierent mode rst in order to make it available. For example, a le must be in Grayscale mode to be converted to Duotone mode. e avail- ability of some Photoshop commands and options will vary depending on the color mode of your document. Some mode conversions can cause noticeable color shifts. For example, if you convert a le from RGB Color mode to CMYK Color mode, printable colors will be substituted for RGB colors. e fewer times you convert a le, the better, as its color data is altered with each conversion change. Some conversions atten layers, such as a conversion to Indexed Color, Multichannel, or Bitmap mode. Other conversions give you the option to preserve layers via a Don’t Flatten button in an alert dialog. Digital cameras and medium- to low-end scan- ners produce RGB images. For faster editing, and in order to access all the lters in Photoshop, we rec- ommend keeping your les in RGB Color mode. In fact, most desktop color inkjet printers, especially those that use six or more ink colors, can process RGB Color les directly from Photoshop. ➤ To “soft-proof ” your RGB document as a simu- lation of CMYK Color mode without perform- ing an actual mode change, see pages 404–405. ptg 4 Chapter 1 details), the colors green to red, and the colors blue to yellow. e lightness and color values can be edited independently of one another. Although Photoshop uses Lab Color to produce conversions between RGB and CMYK color modes internally, there’s rarely a need for Photoshop users like us to convert our les to Lab Color mode. Multichannel images contain multiple 256-level grayscale channels. If you convert an image from RGB Color to Multichannel mode, its Red, Green, and Blue channels are converted to Cyan, Magenta, and Yellow. As a result, the image may become lighter and the contrast may be reduced. Some Photoshop pros assemble individual channels from several images into a single composite image by using this mode, but this takes expertise. With this foundation in color basics, you’re ready to take the plunge into color management. e following is a brief summary of the color modes that a document can be converted to in Photoshop: In Bitmap mode, pixels are either 100% black or 100% white, and no layers, lters, or adjustment commands are available. (To convert a le to this mode, you must convert it to Grayscale mode rst.) In Grayscale mode, pixels are black, white, or up to 254 shades of gray (a total of 256). If you convert a le from a color mode to Gray scale mode and then save and close it, its luminosity (light and dark) values will be preserved, but its color infor- mation will be deleted permanently. In Chapter 13, we’ll show you how to convert a layer to grayscale without changing the document color mode. To produce a duotone, two or more extra plates are added to a grayscale image to enhance its rich- ness and tonal depth. is requires special prepara- tory steps in Photoshop and expertise on the part of your commercial printer. Files in Indexed Color mode contain a single channel, as well as an 8-bit color table (which con- tains a maximum number of 256 colors or shades). When you optimize a le in the GIF format via the Save for Web & Devices dialog, the le is con- verted to this color mode automatically (see pages 423–424). RGB Color A is the most versatile mode of all and the one you’ll use most often. It’s the mode in which digital cameras save your photos, the only mode in which all the Photoshop tool options and lters are accessible, the mode of choice for online output, and the mode of choice for export to video and multimedia programs. In Photoshop, although you can display and edit your les in CMYK Color mode, B we recommend editing them in RGB Color mode, then converting a copy of them to CMYK Color mode only when required for commercial printing or for export to a page layout application. Exceptions to this rule are images that are saved by high-end scanners in CMYK Color mode; keep them as CMYK to preserve their original color data. Lab Color is a three-channel mode that was developed for the purpose of achieving consis- tency among various devices, such as printers and displays. Lab Color les are device-independent, meaning their color denitions stay the same regardless of how each output device denes color. e channels represent lightness (the image A Because the mode of this document is RGB Color, it contains three channels. B We converted the document to CMYK Color mode; now it contains four channels. ptg Color Management 5 Introduction to color management Problems with color inconsistency can arise due to the fact that hardware devices and software packages read or output color dierently. If you were to compare how an image looks in an assort- ment of imaging programs and Web browsers, the colors might look completely dierent in each case, and worse still, may not match the picture you originally shot with your digital camera. Print the image, and you’ll probably nd the results are dif- ferent yet again. In some cases, these dierences might be slight and unobjectionable, but in other cases such color shifts can wreak havoc with your design or turn a project into a disaster! A color management system can prevent most color discrepancies by acting as a color interpreter. It knows how each particular device and program interprets color, and adjusts those colors when necessary. e result is that the colors in your les will display and output more consistently as the les are shuttled among various programs and devices. Applications in Adobe Creative Suite 5 use standardized ICC (International Color Consortium) proles, which tell your color management system how each specic device denes color. Each particular device ca n capture and repro- duce only a limited range (gamut) of colors, which in the jargon of color management is known as the color space. e mathematical description of the color space of each device, in turn, is called its color profile. Furthermore, each input device, such as a camera, attaches its own prole to the les it produces. Photoshop will use that prole in order to display and edit the colors in your docu- ment; or if the document doesn’t contain a prole, Photoshop will use the current working space (a color space you choose for Photoshop) instead. Color management is especially important when the same image is used for multiple purposes, such as for online output and print output. Note: For print output, be sure to consult with your prepress service provider or commercial printer (if you’re using one) about color management to ensure that your color management setup works smoothly with theirs. e “meat” of this chapter consists of instruc- tions for choosing color management options, which we strongly recommend you follow before editing your images in Photoshop. Our instructions are centered on using Adobe RGB as the color space for your image-editing work to create color consis- tency throughout your workow. We’ll show you how to set the color space of your digital camera to Adobe RGB, calibrate your display, specify Adobe RGB as the color space for Photoshop, acquire the proper proles for your inkjet printer and paper type, and assign Adobe RGB as the prole of choice for les that don’t use that color space. You’ll need to focus on color management again when you prepare your le for printing. In Chapter 25 (Print), you will create a soft-proof setting for your particular inkjet printer and paper using the acquired proles, and then use it to view a soft proof of your document onscreen. e prole will also be used for outputting les to a color inkjet printer, a device that expects les to be in RGB color. Finally, we’ll show you how to use the appro- priate proles when outputting either to the Web or to a commercial press. e rst step in color management is to estab- lish Adobe RGB as the color space for your camera. Setting a camera’s color space to Adobe RGB Most high-end, advanced amateur digital cam- eras and digital SLR cameras have an onscreen menu, which you can use to customize how the camera processes digital images. Although we’ll use a Nikon D700 as our representative model for setting a camera to the Adobe RGB color space, you can follow a similar procedure to set the color space for your camera. Note: If you shoot photos in the JPEG format, you should choose Adobe RGB as the color space for your camera, regardless of which model it is. If you shoot raw les, these steps are optional, as you will have the opportunity to assign the Adobe RGB color space when you convert your photos via the Camera Raw plug-in (see page 66). Continued on the following page ptg 6 Chapter 1 To set a camera’s color space to Adobe RGB: 1. On the back of your Nikon camera, press the Menu button to access the menu on the LCD screen, and then, if necessary, press the up or down arrow on the multi selector to select the Shooting Menu tab. 2. On the Shooting Menu, press the down arrow on the multi selector to select the Color Space category A (Canon EOS Rebel cameras label this category as Parameters). Press the right arrow on the multi selector to move to the submenu. 3. Press the down arrow to select Adobe RGB. B 4. Press the OK button to set your choice, C–D then press the Menu button to exit the Menu screen. B We pressed the right arrow, then chose Adobe RGB from the Color Space submenu. A On the Nikon Shooting Menu, we selected the Color Space category. NIKON D700 C After pressing OK, the Color Space for our camera is now Adobe RGB. D On a Canon EOS Rebel, we selected the Parameters category, pressed Set to get to the sub- menu, then chose Adobe RGB from the submenu. CANON EOS REBEL ptg Color Management 7 Calibrating your display Display types ere are two main types of computer displays: a CRT (cathode ray tube, as in a traditional TV set) and the more common LCD (liquid crystal display, or at panel display). e display performance of a CRT uctuates due to its analog technology and the fact that its display phosphors (which produce the glowing dots that you see onscreen) fade over time. A CRT display can be calibrated reliably for only around three years. LCD displays use a grid of xed-sized liquid crystals that lter color coming from a back light source. Although you can adjust only the bright- ness on an LCD (not the contrast), the LCD digital technology oers more reliable color consistency than a CRT, without the characteristic ickering of a CRT. e newest LCD models provide good view- ing angles, display accurate color, use the desired daylight temperature of 6500K for the white point (see below), and are produced under tighter manu- facturing standards than CRTs. Moreover, the color prole that’s provided with an LCD display (and that is installed in your system automatically) usu- ally describes the display characteristics accurately. ➤ Both types of displays lose calibration gradu- ally, and you may not notice the change until the colors are way o. To maintain the color consistency of your display, stick to a regular monthly calibration schedule. ankfully, our calibration software reminds us to recalibrate our display via a monthly onscreen alert. Understanding the calibration settings r e e b a s i c c h a r a c t e r i s t i c s a r e a d j u s t e d w h e n a display is calibrated: e brightness (white level) is set to a consistent working standard; the contrast (dark level) is set to the maximum value; and a neutral gray (gray level) is established using equal values of R, G, and B. To adjust these characteris- tics, calibration devices evaluate the white point, black point, and gamma in the display. ➤ e white point data enables the display to project a pure white, which matches an industry-standard color temperature. Photographers favor using D65/6500K as the temperature setting for the white point. ➤ e black point is the darkest black a display can project. All other dark shades are lighter than this darkest black, which ensures that shadow details display properly. ➤ e gamma denes how midtones are dis- played onscreen. A gamma setting of 1.0 repro- duces the linear brightness scale that is found in nature. Human vision, however, responds to brightness in a nonlinear fashion, so this setting makes the screen look washed out. A higher gamma setting redistributes more of the midtones into the dark range, which our eyes are more sensitive to, and produces a more natural-looking image. Photography experts recommend using a gamma setting of 2.2 for both Windows and Macintosh displays. Buying a calibration device e only way to calibrate a display properly is by using a hardware calibration device, which pro- duces a prole containing the proper white point, black point, and gamma settings for your display. e Adobe color management system, in turn, will use that prole to display colors in your Photoshop document more accurately. If you’re shopping for a calibration device, you’ll notice a wide range in cost, from a $100 to $300 colorimeter to a much more costly, but more precise, high-end professional gadget, such as a spectrophotometer. A colorimeter and its step- by-step wizard tutorial will enable you to calibrate your display more precisely than you could by using subjective “eyeball” judgments. Among moderately priced calibrators, our informal reading of hardware reviews and other industry publications has yielded the follow- ing as some of the current favorites: Spyder3Pro and Spyder3Elite by Datacolor; i1 Display2 and i1 Display LT by X-Rite; and hueyPro, which was developed jointly by PANTONE and X-Rite. Note: If, after calibrating your display, you intentionally or unintentionally adjust the display’s brightness and contrast settings or change the room lighting (or repaint your walls!), remember to recalibrate it! For Mac OS users who don’t have a calibration device, your system supplies a display calibra- tion utility; look for it in System Preferences > Displays > Color. Click Calibrate and follow the instructions that appear onscreen. ptg 8 Chapter 1 e steps outlined here apply loosely to the three hardware display calibrators that are mentioned on the preceding page. We happen to use Spyder3Pro. To calibrate your display using a hardware device: 1. Set the room lighting to the level that you nor- mally use for work. If you have a CRT, let it warm up for 30 minutes for the display to stabilize. 2. Increase the brightness of your display to its highest level. In the Mac OS, if you have an Apple display, choose System Preferences > Displays and drag the Brightness slider to the far right. For a third-party display or any Windows display, use either a mechanical button on the display or a menu command in the OnScreen Display (OSD). 3. Launch the calibration application that you’ve installed, then follow the straightforward instruc- tions on the step-by-step wizard screens. A–B You will need to tell the application the follow- ing important information: your display type (CRT or LCD), the white point to be used (choose D65/6500K), and the desired gamma value (choose 2.2 for both Windows and Macintosh). For a CRT display, you may see a few more instructional screens requesting further display setting choices. 4. After entering your display information ( A , next page), you’ll be prompted to drape the col- orimeter (hardware calibration sensor) over the monitor ( B , next page). For an LCD, if a bae is included with the calibration device, clip it on to prevent the suction cups from touching and potentially damaging the screen. Follow the instructions to align the sensor with the image onscreen. Click OK or Continue to initiate the series of calibration tests, which will take from 5 to 8 minutes. 5. After removing the calibration sensor, you’ll be prompted to name your new display prole ( C , next page). Include the date in the prole name, for your own reference. e application will place the new prole in the correct loca- tion for your Windows or Macintosh operating system. e wizard will step you through one or two more screens, and then you’re done. When launched, Photoshop will automatically be aware of the new display prole. A After launching the Sypder3Pro applica- tion, we answered questions on the Display Type screens to tell the wizard software what type of monitor we have and what features it has. We clicked Next to progress from screen to screen. B On this Methods of Attachment screen, we clicked No Suction Cup. ptg Color Management 9 A e r e s u l t i n g s e t t i n g s a p p e a r e d on this Current Settings screen. Click Continue with ese Settings. Note: If you have already used the device to calibrate your monitor, a screen entitled CheckCAL will appear instead of this one. Click CheckCAL – Check Current Calibration. B When this Measuring Display screen appeared, we draped the colorimeter over the monitor and aligned it with the onscreen image, then clicked Continue to initiate the actual calibration process. C When the calibration was nished, we clicked Next, and this Specify Prole Name screen appeared. In our prole name, we included the monitor name and the current date. After we clicked Next again, the SpyderProof screen appeared. We clicked Switch to compare the pre- and postcalibration results. Finally, we clicked Next, chose Quit, then clicked Next one last time to exit the software. . icon yet, open the Adobe Photoshop CS5 folder in the Applications folder, then drag the Adobe Photoshop CS5 application icon into the Dock.) Open the Adobe Photoshop CS5 folder in the Applications. . . . . . . . 14 Changing color profi les . . . . . . . . . . 16 1 Welcome to Photoshop! In this chap- ter, you’ll launch the application and familiarize yourself with Photoshop color. All Programs, then click Adobe Photoshop CS5 (64-bit). Double-click a Photoshop le icon. To launch Photoshop in the Mac OS: Do one of the following: Click the Photoshop icon in the Dock. (If