Photoshop cs5 missing manual_1

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Photoshop cs5 missing manual_1

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Với tính năng mới như Content-Aware Fill và Puppet Warp, Photoshop CS5 tuyệt vời hơn, bao gồm Photoshop từ một quan điểm thực tế, với các mẹo, thủ thuật và lời khuyên thực tế bạn có thể sử dụng hàng ngày để chỉnh sửa hình ảnh và tạo các tài liệu đẹp.

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  1. Selection Basics Figure 4-1: To let you know an area is selected, Photoshop surrounds it with tiny, moving dashes that look like marching ants. Here you can see the ants running around the armadillo. (FYI, the nine-banded armadillo is the state animal of Texas. Aren’t you glad you bought this book?) Here are the commands you’ll use most often when you make selections: • Select All. This command selects your whole document and places marching ants around the perimeter, which is helpful when you want to copy and paste an entire image into another program or create a border around a photo (see page 183). To run this command, go to Select➝All or press �-A (Ctrl+A on a PC). • Deselect. To get rid of the marching ants after you’ve finished working with the selection, choose Select➝Deselect or press �-D (Ctrl+D). Alternatively, if you’ve got one of the selection tools activated in the Tools panel, you can click once outside the selection to get rid of your selection. • Reselect. To resurrect your last selection, choose Select➝Reselect or press �-Shift-D (Ctrl-Shift-D). This command reactivates the last selection you made, even if it was five filters and 20 brushstrokes ago (unless you’ve used the Crop and Type tools, which render the Reselect command powerless). Reselect- ing is helpful if you accidentally deselect a selection you’ve been working on for a long time. (The Undo command [�-Z or Ctrl+Z] can also help you in that situation.) • Inverse. This command, which you run by going to Select➝Inverse or pressing �-Shift-I (Ctrl-Shift-I), lets you flip-flop a selection to select everything you didn’t select before. You’ll often find it easier to select what you don’t want and then inverse the selection to get what you do want (see the box on page 155). • Load a layer as a selection. When talking to people about Photoshop, you’ll often hear the phrase “load as a selection,” which is (unavoidable) Photoshop- speak for activating a layer that contains the object you want to work with and then summoning the marching ants so they run around that object; that way, chapter 4: selections: choosing what to edit 137
  2. Selecting by Shape whatever you do next affects only that object. To load everything that lives on a single editable layer as a selection, mouse over to the Layers panel and �-click (Ctrl+click) the layer’s thumbnail (page 78); you don’t need to have the layer selected. Photoshop responds by putting marching ants around everything on that layer. Alternatively, you can Ctrl-click (right-click on a PC) the layer’s thumbnail and then choose Select Pixels from the resulting shortcut menu. Tip: Although you can find most of the commands in this list in the Select menu at the top of your screen (except for loading a layer as a selection), you should memorize their keyboard shortcuts if you want to be smokin’ fast in Photoshop. These next three items live in the Select menu, but they don’t actually call up march- ing ants. Instead, they tell Photoshop to select entire layers (for the lowdown on layers, see Chapter 3): • All Layers. Use this command if you want to select every layer in your docu- ment (so you can move several layers at once, for example). To select all layers, choose Select➝All Layers or press �-Option-A (Ctrl+Alt+A). • Deselect Layers. This command does the exact opposite of the previous one: It deselects all the layers in your Layers panel, leaving nary a layer highlighted. To run it, choose Select➝Deselect Layers. • Similar Layers. Choose this command if you want to select all layers of the same kind (page 76 lists the different types of layers). For example, say you want to change the font in all the Type layers in your document. Just select a Type layer and then choose Select➝Similar. Photoshop selects all your Type layers and highlights them in the Layers panel so you can modify them all at once. (See Chapter 14 for more on Type layers.) Tip: When you move objects around with the Move tool, you can enlist Photoshop’s help in selecting individual layers by turning on Auto-Select in the Options bar. With this setting on, as you click an object in your document, Photoshop tries to guess which layer it’s on and select that layer for you. Now it’s time to discuss the tools you can use to make selections. Photoshop has a ton of ’em, so in the next several pages, you’ll find them grouped according to which kind of selections they’re best at making. Selecting by Shape Selections based on shape are probably the easiest ones to make. Whether the object you need to grab is rectangular, elliptical, or rectangular with rounded corners, Pho- toshop has just the tool for you. You’ll use the first couple of tools described in this section often, so think of them as your bread and butter when it comes to making selections. Photoshop CS5: The Missing Manual 138
  3. Selecting by Shape The Rectangular and Elliptical Marquee Tools Photoshop’s most basic selection tools are the Rectangular and Elliptical Marquees. Anytime you need to make a selection that’s squarish or roundish, reach for these little helpers, which live at the top of the Tools panel, as shown in Figure 4-2. Figure 4-2: You’ll spend loads of time making selections with the Rectangular and Elliptical Marquee tools. To summon this pop-up menu, click the second item from the top of the Tools panel and hold down your mouse button until the menu appears. To make a selection with either marquee tool, just grab the tool by clicking its icon in the Tools panel or by pressing M and then mouse over to your document. When your cursor turns into a tiny + sign, drag across the area you want to select (you’ll see the marching ants appear as soon as you start to drag). Photoshop starts the selec- tion where you clicked and continues it in the direction you drag as long as you hold down the mouse button. When you’ve got marching ants around the area you want to select, release the mouse button. You can use a variety of tools and techniques to modify your selection, most of which you can find in the Options bar (Figure 4-3). For example, you can: • Move the selection. Click anywhere within the selected area and drag to an- other part of your document (your cursor turns into a tiny arrow) to move the selection where you want it. Tip: You can move a selection as you’re drawing it by moving your mouse while pressing the mouse button and the space bar. When you’ve got the selection where you want it, release the space bar and continue drawing the selection. • Add to the selection. When you click the “Add to selection” button in the Op- tions bar (see Figure 4-3) or press and hold the Shift key, Photoshop puts a tiny + sign beneath your cursor to let you know it’ll add whatever you select to your current selection. This mode is handy when you’ve selected most of what you want but notice that you missed a spot. Instead of starting over, you can switch to this mode and draw around that area as if you were creating a new selection. You can also use this mode to select areas that don’t touch each other, like the irises in your dog’s eyes (see page 456). chapter 4: selections: choosing what to edit 139
  4. Selecting by Shape Figure 4-3: New selection Using the buttons in the Add to selection Options bar, you can add to Subtract from selection or subtract from a selection, Intersect with selection as well as create a selection from two intersecting areas. Since all selections begin at the point where you first click, you can easily select one of these doors by drag- ging diagonally from the top-left corner to the bottom right as shown here. You can tell from the tiny + sign next to the crosshair-shaped cursor that you’re in “Add to selection” mode, so this figure now has two selec- tions: the blue door and the red door. • Subtract from the selection. Clicking the Options bar’s “Subtract from selec- tion” button (also shown in Figure 4-3) or pressing and holding the Option key (Alt on a PC) has the opposite effect. You see a tiny – sign beneath your cursor to let you know you’re in this mode. Mouse over to your document and draw a box (or oval) around the area you want to deselect. • Intersect one selection with another. If you click the “Intersect with selection” button after you draw a selection, Photoshop lets you draw another selection that overlaps the first; the marching ants then surround only the area where the two selections overlap. It’s a little confusing, but don’t worry because you’ll Photoshop CS5: The Missing Manual 140
  5. Selecting by Shape rarely use this mode (if at all). The keyboard shortcut is Shift-Option (Shift+Alt on a PC). Photoshop puts a tiny multiplication sign (×) beneath your cursor when you use this mode. • Feather. If you want to soften the edges of your selection so that it blends into the background or another image, use feathering. You can enter a value in pixels in this field before you create the selection. As you’ll learn later in this chapter, feathering a selection lets you gently fade one image into another. See the box on page 145 for more on feathering. • Anti-alias. Turn on the Anti-alias checkbox to make Photoshop smooth the color transition between the pixels around the edges of your selection and the pixels in the background. Like feathering, anti-aliasing softens your selection’s edges slightly so that they blend better, though you can’t control the amount of softening Photoshop applies. It’s a good idea to leave this checkbox turned on unless you want your selection to have super crisp—and possibly jagged and blocky—edges. • Style. If you want to constrain your selection to a fixed size or aspect ratio (so that the relationship between its width and height stays the same), you can se- lect Fixed Width or Fixed Ratio from the Style pop-up menu and then enter the size you want in the resulting width and height fields. (Be sure to enter a unit of measurement into each field, such as px for pixels.) If you leave the Normal option selected, you can draw any size selection you want. Here’s how to select two doors in the same photo, as shown in Figure 4-3: 1. Click the marquee tool icon in the Tools panel and choose the Rectangular Marquee from the pop-up menu (shown in Figure 4-2). The Tools panel remembers which marquee tool you last used, so you’ll see that tool’s icon on top of the selection tools pop-up menu. If that’s the one you want to use, just press M to activate it. If not, in the Tools panel, click and hold whichever marquee tool is showing until the pop-up menu appears and then choose the tool you want. Tip: To cycle between the Rectangular and Elliptical Marquee tools, press M to activate the marquee toolset and then press Shift-M to activate each one in turn. If that doesn’t work, make sure that a gremlin hasn’t turned off the preference that makes this trick possible. Choose Photoshop➝Preferences➝General (Edit➝Preferences➝General on a PC) and make sure the “Use Shift Key for Tool Switch” checkbox is turned on. 2. Drag to draw a box around the first door. To select the blue door shown in Figure 4-3, click its top-left corner and drag di- agonally toward its bottom-right corner. When you get the whole door in your selection, release the mouse button. Don’t worry if you don’t get the selection in exactly the right spot; you can move it around in the next step. chapter 4: selections: choosing what to edit 141
  6. Selecting by Shape 3. Move your selection into place if necessary. If you need to move the selection, just click inside the selected area (your cursor turns into a tiny arrow) and drag the selection box where you want it. You can also use the arrows on your keyboard to nudge the selection in one direction or another (you don’t need to click it first). 4. Press the “Add to selection” button in the Options bar and then select the second door by drawing a selection around it. Photoshop lets you know that you’re in “Add to selection” mode by placing a tiny + sign beneath your cursor. Once you see it, mouse over to the second door and drag diagonally from its top-left corner to its bottom right, as shown in Figure 4-3. If you need to move this second selection around, do that before you release the mouse button or you’ll end up moving both selections instead of just one. To move a selection while you’re drawing it, hold down your mouse button, press and hold the space bar, and then move your mouse to move the selection. When you’ve got the selection in the right place, release the space bar—but keep holding the mouse button—and continue dragging to draw the selection. This maneuver feels a bit awkward at first, but you’ll get used to it with practice. Congratulations! You’ve just made your first selection and added to it. Way to go! Tip: To draw a perfectly square or circular selection, press and hold the Shift key as you drag with the Rectangular or Elliptical Marquee tool, respectively. If you want to draw the selection from the center out- ward (instead of from corner to corner), press and hold the Option key (Alt on a PC). If you want to draw a perfectly square or circular selection from the center outward, press and hold Shift-Option (Shift+Alt) as you drag with either tool. Whew—that’s a lot of keys! Be sure to use this trick only on new selections—if you’ve already got a selection, the Shift key pops you into “Add to selection” mode. Creating a soft vignette The Elliptical Marquee tool works just like the Rectangular Marquee tool except that it draws round or oval selections. It’s the perfect tool for selecting eyes, circling yourself in a group photo (page 184), or creating the ever-popular, oh-so-romantic, soft oval vignette shown in Figure 4-4. Photoshop CS5: The Missing Manual 142
  7. Selecting by Shape Figure 4-4: By feathering a selection you’ve made with the Elliptical Marquee tool and adding a layer mask (page 113), you can create a quick two-photo collage like this one. Wedding photogra- phers and moms—not to mention armadillo fans— love this kind of thing! If you forget to feather your selection before you add a layer mask, not to worry: you can always use the Masks panel (page 120) to do it after the fact. Just click to select the mask thumbnail and then choose Window➝Masks. When the Masks panel opens, drag the Feather slider slightly to the right to give it a soft edge. Once you get the hang of this technique, try creating it using the Ellipse Shape tool set to draw in path mode instead, as described in the section on shape tools later in this chapter. It’s a little bit quicker and slightly more efficient! Here’s how to create a soft oval vignette: 1. Open two images and combine them into one document. Simply drag one image from its Layers panel into the other document’s window, as shown on page 101. 2. Reposition the layers so the soon-to-be-vignetted photo is at the top of the Layers panel. Over in the Layers panel, make sure that both layers are editable so you can change their stacking order. If you see a tiny padlock to the right of either layer’s name, double-click that layer in the Layers panel to make it editable. Then drag the layer containing the photo you want to vignette (in Figure 4-4, that’s the picture of the armadillo) to the top of the Layers panel. chapter 4: selections: choosing what to edit 143
  8. Selecting by Shape 3. Grab the Elliptical Marquee tool and select the part of the image you want to vignette (here, the armadillo’s head). Peek at your Layers panel to make sure the correct photo layer is selected (the armadillo) and position your mouse near the center of the image. Press and hold the Option key (Alt on a PC), mouse over to the image, and drag to draw an oval-shaped selection from the inside out. When you’ve got the selection big enough, release the Option (or Alt) key and your mouse button. 4. Feather the selection’s edges by clicking the Refine Edge button in the Options bar. In the resulting dialog box, make sure all the sliders are set to 0 and then drag the Feather slider to the right. If you want to see what the feathered edge will look like, release your mouse button and take a peek at your document—you’ll see the newly softened edge against a temporary white background. If you want to preview the feather against a different background, click any of the other pre- view buttons toward the bottom of the dialog box. (Page 166 covers the Refine Edge dialog box in greater detail.) When it looks good, click OK to close the dialog box. 5. Hide the area outside the selection with a layer mask. You could simply inverse the selection (page 155) and then press the Delete key (Backspace on a PC) to zap the area outside the selection, but that’d be mighty reckless. What if you changed your mind? You’d have to undo several steps or— curses—start over completely! A less destructive and more flexible approach, which you learned about back on page 113, is to hide the area outside the selec- tion with a layer mask. Over in the Layers panel, make sure you have the correct layer selected (in this case, the armadillo) and then add a layer mask by clicking the tiny circle-within-a-square icon at the bottom of the Layers panel (you can also use the Mask panel’s Feather slider to soften the mask’s edge, if you hap- pened to skip the previous step of feathering the selection). Photoshop hides everything outside the selection area, letting you see through to the bluebonnet layer below. Beautiful! That armadillo looks right at home, doesn’t he? You’ll want to memorize these steps because this method is perhaps the easiest—and most romantic!—way to combine two images into a new and unique piece of art (although starting on page 146 you’ll learn how to use the vector Shape tools to do the same thing). The Single Row and Column Marquee Tools The Marquee toolset also contains the Single Row Marquee and Single Column Marquee tools, which can select exactly one row or one column’s worth of pixels, spanning either the width or the height of your document. You don’t need to drag with your mouse to create a selection with these tools; just click once in your docu- ment and the marching ants appear. Photoshop CS5: The Missing Manual 144
  9. Selecting by Shape Now, you may be asking, “When would I want to do that?” Not often, it’s true, but consider these circumstances: • Mocking up a web page design. If you need to simulate a column or row of space between certain areas in a web page, you can use either tool to create a selection that you fill with the website’s background color, or you can just delete the existing pixels by pressing the Delete key (Backspace on a PC). FReQUeNtLY ASKed QUeStIoN The Softer Side of Selections However, by far the best method is to use the Refine Edge How come my selections always have hard edges? Can I dialog box, which lets you see what the feathered edge make them soft instead? will look like before you commit to it. To use this method, When you first install Photoshop, any selection you make draw a selection and then head up to the Options bar and has a hard edge, but you can apply feathering to soften click the Refine Edge button. The dialog box that appears it up. Feathered selections are perfect for blending one has five preview buttons that show a loopy metallic ring. image—or a portion of an image—into another, as in the Click one of these buttons to put a temporary background soft oval vignette effect, an oldie but goody shown on behind your selection (making its edges more visible) and page 142. You can also feather a selection when you re- then adjust the Feather slider to your liking. Once you’ve touch an image, so the retouched area fades gently into got the feather just right, press OK to dismiss the dialog the surrounding pixels, making it look more realistic. This box. technique is especially helpful when you’re whitening teeth Note that the settings in the Refine Edges dialog box are (page 436), fixing animal white-eye (page 456), or swap- “sticky,” meaning that once you change them, they stay ping heads (page 179). You can feather a selection, either changed until you modify them again. For that reason, you before or after you’ve created it, in a variety of ways: should set the other sliders to 0 to keep your selection from After you choose a selection tool from the Tools panel—but changing in unexpected ways. (Page 166 has more about before you draw your selection—hop up to the Options bar the Refine Edge dialog box.) and enter a Feather amount in pixels (you can enter whole You won’t notice a change to your marching ants (unless numbers or decimals, like 0.5). Feathering by just a few you enter a huge amount of feathering on a rectangular pixels blurs and softens the selection’s edges only slightly, selection, which makes the corners look rounded), but, rest whereas increasing the Feather setting creates a wider, assured, Photoshop has indeed feathered your selection. more intense blur and a super-soft edge. Once you delete the rest of the image (or hide it with a After you draw the selection, you can change the Feather layer mask, as shown on page 143), you’ll see the newly setting either by choosing Select➝Modify➝Feather and softened edges. then entering a number of pixels or by Ctrl-clicking (right- clicking on a PC) the selection and choosing Feather from the resulting shortcut menu. chapter 4: selections: choosing what to edit 145
  10. Selecting by Shape • Stretching an image to fill a space. If you’re designing a web page, for example, you can use these tools to extend the image by a pixel or two. Use either tool to select a row of pixels at the bottom or side of the image, grab the Move tool by pressing V, and tap the arrow keys on your keyboard while holding the Option key (Alt on a PC) to nudge the selection in the direction you need and duplicate it at the same time. However, a better option might be to use Content-Aware Scale (see page 258). • Making an image look like it’s melting or traveling through space at warp speed. You can use either tool to create a selection and then stretch it with the Free Transform tool (see Figure 4-5). Figure 4-5: To achieve the melting strawberry look shown here, start by using the Single Row Marquee to select a row of pixels. Then “jump” the selec- tion onto its own layer by pressing �-J (Ctrl+J on a PC). Next, summon the Free Transform tool by pressing �-T (Ctrl+T), and drag one of the square, white center handles downward. Unfortunately you can’t get to the Single Row and Single Column Marquee tools with a keyboard shortcut; you’ve got to activate them in the Tools panel instead. The Vector Shape Tools Okay, technically, vector shapes aren’t selection tools at all, but you can use them to create selections (turn to page 551 to learn more about vector shapes). Once you get the hang of using them (as this section shows you) you’ll be reaching for ’em all the time. Photoshop CS5: The Missing Manual 146
  11. Selecting by Shape Perhaps the most useful of this bunch is the Rounded Rectangle tool. If you ever need to select an area that’s rectangular but has rounded corners, the Rounded Rect- angle tool is your best bet. If you’re creating an ad for a digital camera, say, you can use this technique in a product shot to swap the image shown on the camera’s display screen with a different image. Or more practically, you can use it to give your photos rounded corners, as shown in Figure 4-6. Figure 4-6: If you’re tired of boring, straight corners on your images, use the Rounded Rectangle tool to produce smooth corners like the ones shown here. Here’s how to round the corners of your photos: 1. Open a photo and double-click the Background layer to make it editable. Because you’ll add a mask to the photo layer in step 6, you need to make sure the Background layer is unlocked or Photoshop won’t let you add the mask. 2. Select the Rounded Rectangle tool from the Tools panel. Near the bottom of the Tools panel is the Vector Shape toolset. Unless you’ve previously selected a different tool, you’ll see the Rectangle tool’s icon. Click the icon and hold down your mouse button until the pop-up menu appears and then choose the Rounded Rectangle tool. chapter 4: selections: choosing what to edit 147
  12. Selecting by Shape Tip: To cycle through all the shape tools, press Shift-U repeatedly. 3. In the Options bar, click the Paths mode button and change the Radius field to 40 pixels. As you’ll learn on page 551, the vector Shape tools can operate in various modes, which you set in the Options bar. For this particular technique, you need to make sure that the Rounded Rectangle tool is in Paths mode (the but- ton looks like a square with a tiny dot on each corner with a pen in the center). Next, change the number in the Options bar’s Radius field, which controls how rounded the image’s corners will be: the lower the number, the less rounded; the higher the number, the more rounded. This field was set to 40 pixels to create the corners shown in Figure 4-6. 4. Draw a box around the image. Mouse over to your image and, starting in one corner, drag diagonally to draw a box around it. When you let go of the mouse button, Photoshop creates a thin gray line that appears atop your image called a path (you’ll learn more about paths in Chapter 13). If you need to move the box, while you’re drawing it, press and hold the space bar. If you want to move it after you’ve drawn it, press A to grab the Path Selection tool (it looks like a black arrow and lives below the Type tool in the Tools panel), click the path to select it, and then drag to move it wherever you want. 5. Hide the area outside the path by adding a layer mask. Over in the Layers panel, click the photo layer once to select it and then add a vector layer mask by �-clicking (Ctrl-clicking) the tiny circle-within-a-square icon at the bottom of the Layers panel. Photoshop hides the old, boring square photo edges. Why a vector mask, you ask? Because the path you drew with the Shape tool is vector in nature, not pixel-based. As you learned on page 52, you can resize a vector without losing quality anytime you want by selecting it and using Free Transform (page 263). Sweet! For more on vector masks, skip ahead to page 572. Who knew that giving your photo rounded corners was so simple? Tip: You can use the same technique with the Ellipse Shape tool to create the vignette shown in the previ- ous section. You can also feather the mask after you’ve made it by choosing Window➝Masks to open the Masks panel, and then dragging the Feather slider to the right. Photoshop CS5: The Missing Manual 148
  13. Selecting by Color Selecting by Color In addition to giving you tools to select areas by shape, Photoshop lets you select areas by color. This option is helpful when you want to select a chunk of an image that’s fairly uniform in color, like someone’s skin, the sky, or the paint job on a car. Photoshop has lots of tools to choose from, and in the next several pages, you’ll learn how to pick the one that best suits your needs. The Quick Selection Tool The Quick Selection tool is shockingly easy to use and lets you create complex selec- tions with a few strokes of an adjustable brush. As you paint with the Quick Selec- tion tool, your selection expands outward to encompass pixels similar in color to the ones you’re brushing across. It works insanely well if there’s a fair amount of contrast between what you want to select and everything else. This tool lives in the same toolset as the Magic Wand (page 151), as you can see in Figure 4-7. Figure 4-7: Add to selection New Selection Subtract from selection When you activate the Quick Selection tool, the Options bar sports buttons that let you create a new selection and add to or subtract from the current selection. You can press the W key to activate the Quick Selection tool. To switch between it and the Magic Wand, press Shift-W. To use this wonderfully friendly tool, click anywhere in the area you want to select or drag the brush cursor across it, as shown in Figure 4-8. When you do that, Photo- shop thinks for a second and then creates a selection based on the color of the pixels you clicked or brushed across. The size of the area Photoshop selects is proportional to the size of the brush you’re using: a larger brush creates a larger selection. You can adjust the Quick Selection tool’s brush size just like any other brush: by choosing a new size from the Brush Preset picker in the Options bar, or by using the keyboard shortcut discussed in the Tip on page 117. (Chapter 12 covers brushes in detail.) For the best results, use a hard-edged brush to produce defined edges (instead of the slightly transparent edges produced by a soft-edge brush) and turn on the Auto- Enhance setting shown in Figure 4-7 and discussed in the box on page 151. chapter 4: selections: choosing what to edit 149
  14. Selecting by Color Figure 4-8: If the color of the objects you want to select differs greatly from the color of their background, like these chili peppers, take the Quick Selection tool for a spin. With this tool activated, you can either single-click the area you want to select or drag your cursor (circled) across the area as if you were painting. When the tool is in “Add to selection” mode, you see a tiny + sign inside the cursor, as shown here. This mode lets you add to an existing selection or make multiple selections. When you activate the Quick Selection tool, the Options bar offers three modes (see Figure 4-7): • New selection. When you first grab the Quick Selection tool, it’s automatically set to create a brand-new selection, which is helpful since creating a new selec- tion is sort of the whole point. • Add to selection. Once you’ve clicked or made an initial brushstroke, the Quick Selection tool automatically goes into “Add to selection” mode (indicated by the tiny + sign inside the cursor, as shown in Figure 4-8). Now Photoshop adds any additional areas you brush over or click to your current selection. If you don’t like the selection Photoshop has created and want to start over, press �-Z (Ctrl+Z on a PC) to undo it, or click the Options bar’s “New selection” button and then brush across the area again. (The old selection disappears as soon as you start to make a new one.) To get rid of the marching ants altogether, choose Select➝Deselect. • Subtract from selection. Adding to a selection can make Photoshop select more than you really want it to. If you have this problem, click the “Subtract from selection” button (a tiny – sign appears in your cursor) and then simply paint across the area you don’t want selected to make Photoshop exclude it. Note: To get the most out of the Quick Selection tool, you’ll probably need to do a fair amount of adding to and subtracting from your selections. Keyboard shortcuts can help speed up the process: Press and hold the Shift key to enter “Add to selection” mode. Press and hold the Option key (Alt on a PC) to enter “Subtract from selection” mode. If these shortcuts sound familiar, they should—they’re identical to the marquee tools’ keyboard shortcuts. Photoshop CS5: The Missing Manual 150
  15. Selecting by Color • Brush Size. Use a larger brush to select big areas and a smaller brush to select small or hard-to-reach areas. As explained earlier, you’ll get better results with this tool by using a hard-edged brush instead of a soft-edged one. Tip: You can change a brush cursor’s size by dragging: press Ctrl-Option and drag to the left or right (right-click+Alt on a PC). You can also decrease the brush size by pressing the left bracket key ([ ) or increase it by pressing the right bracket key ( ]). • Sample All Layers. This setting is initially turned off, which means Photoshop examines only the pixels on the active layer (the one that’s selected in your Layers panel). If you turn on this setting, Photoshop examines the whole enchilada—ev- erything in your document—and grabs all similar pixels no matter which layer they’re on. • Auto-Enhance. Because the Quick Selection tool makes selections extremely fast, their edges can end up looking blocky and imperfect. To tell Photoshop to take its time and think more carefully about the selections it makes, turn on the Options bar’s Auto-Enhance checkbox. This feature gives your selections smoother edges, but if you’re working with a really big file, you could do your taxes while it’s processing. The box below has tips for using this feature. WoRKARoUNd WoRKSHop Smart Auto-Enhancing checkbox turned off until you’re almost finished making the The Quick Selection tool’s Auto-Enhance feature is pretty selection. When you’ve got just one or two brushstrokes left cool, but it’s a bit of a processing hog and you need a fast to complete your selection, turn on the checkbox to make computer to use it on anything but the smallest images. If Photoshop re-examine all the edges it’s already created for you have an older computer, you may have better luck us- your selection to see if it needs to extend them. That way, ing the Refine Edge dialog box (page 166) to create selec- you get the benefit of using Auto-Enhance and keep your tions with smooth edges. computer running quickly until the last possible moment. That being said, you don’t have to avoid Auto-Enhance al- together. When you’re working with a large file (anything over 5 MB), try leaving the Options bar’s Auto-Enhance The Magic Wand The Magic Wand lets you select areas of color by clicking (rather than dragging). It’s in the same toolset as the Quick Selection tool, and you can grab it by pressing Shift- W (it looks like a wizard’s wand, as shown back in Figure 4-7). Use the Magic Wand to select solid-colored backgrounds or large bodies of similar color, like a cloudless sky, with just a couple of clicks. The Quick Selection tool, in contrast, is better at selecting objects rather than big swaths of color. chapter 4: selections: choosing what to edit 151
  16. Selecting by Color When you click once with the Magic Wand in the area you want to select, Photoshop magically (hence the name) selects all the pixels on the currently selected layer that are both similar in color and touching one another (see page 153 to learn how to tweak this behavior). If the color in the area you want to select varies a bit, Photo- shop may not select all of it. In that case, you can add to the selection either by press- ing and holding the Shift key as you click nearby areas or by modifying the Magic Wand’s tolerance in the Options bar as described later in this section and shown in Figure 4-9. To subtract from your selection, just press and hold the Option key (Alt on a PC) while you click the area you don’t want included. Figure 4-9: With its tolerance set to 32, the Magic Wand did a good job of selecting the sky behind downtown Dallas. You’ve got several ways to select the spots it missed like the area circled at the bot- tom left: You can add to the selection by pressing the Shift key as you click in that area, increase the tolerance setting in the Options bar and then click the sky again to create a new selection, or skip to page 154 to learn how to expand your selection with the Grow and Similar commands. When you activate the Magic Wand, the Options bar lets you adjust the following settings: • Tolerance. This setting controls the Magic Wand’s sensitivity—how picky the tool is about which pixels it considers similar in color. If you increase this set- ting, Photoshop gets less picky (in other words, more tolerant) and selects ev- ery pixel that could possibly be described as similar to the one you originally clicked. If you decrease this setting, Photoshop gets pickier and selects only pix- els that closely match the original. Out of the box, the tolerance is set to 32, but it can go all the way up to 255. (If you set it to 0, Photoshop selects only pixels that exactly match the one you clicked; if you set it to 255, the program selects every color in the image.) It’s usually a good idea to keep the tolerance set fairly low (somewhere between 12 and 32); you can always click an area to see what kind of selection you get, increase the tolerance if you need to, and then click the area again (or add to the selection using the Shift key, as described above). Photoshop CS5: The Missing Manual 152
  17. Selecting by Color Note: When you adjust the Magic Wand’s tolerance, Photoshop won’t automatically rethink your current selection. You have to click the area again to make Photoshop recalculate its selection. • Anti-alias. Leave this setting turned on to make Photoshop soften the edges of your selection ever so slightly. If you want a super-crisp edge, turn it off. • Contiguous. You’ll probably want to leave this checkbox turned on; it makes the Magic Wand select pixels that are adjacent to one another. If you turn this setting off, Photoshop goes hog wild and selects all similar-colored pixels no matter where they are. • Sample all layers. If your document has multiple layers and you leave this checkbox turned off, Photoshop examines only pixels on the active layer and ig- nores the pixels on other layers. If you turn this setting on, Photoshop examines the whole image and selects all pixels that are similar in color, no matter which layer they’re on. GeM IN tHe RoUGH Changing the Magic Wand’s Sample Size However, the menu’s other options cause it to look at the Did you know you can change the way the Magic Wand original pixel and average it with the colors of surrounding calculates which pixels to select? Of course, you didn’t; pixels. that’s because the setting that controls the Magic Wand’s selections appears only when you have the Eyedropper Depending on which option you choose, you can make the tool selected. (Makes perfect sense, doesn’t it?) You can Magic Wand average the pixel you clicked plus the eight read about the Eyedropper tool on page 495, but here’s surrounding pixels (by choosing “3 by 3 Average”) or as what you need to know about it to tweak the Magic Wand: much as the surrounding 10,200 pixels (by choosing “101 by 101 Average”). The “3 by 3 Average” setting works well Over in the Tools panel, select the Eyedropper tool (its for most images. If you need to select a really big area, you icon, not surprisingly, looks like an eyedropper; it lives be- can experiment with one of the higher settings like “31 by neath the Crop tool). When you do that, a Sample Size 31 Average”. pop-up menu containing a slew of settings appears in the Options bar. After you make your selection, simply activate the Magic Wand and then click somewhere in your image to see the From the factory, the Sample Size menu is set to Point effect of the new setting. It’s that simple. Sample, which makes the Magic Wand look only at the color of the pixel you clicked when determining its selection. Expanding your selection Sometimes the Magic Wand makes a nearly perfect selection, leaving you with pre- cious few pixels to add to it. If this happens, it simply means that the elusive pixels are just a little bit lighter or darker in color than what the Magic Wand’s tolerance setting allows for. You could Shift-click the elusive areas to add them to your selection, chapter 4: selections: choosing what to edit 153
  18. Selecting by Color but the Select menu has a couple of options that can quickly expand the selection for you: • Choose Select➝Grow to make Photoshop expand your selection to all similar- colored pixels adjacent to the selection (see Figure 4-10, top). • Choose Select➝Similar to make Photoshop select similar-colored pixels through- out the whole image even if they’re not touching the original selection (see Figure 4-10, bottom). Note: Because both these commands base their calculations on the Magic Wand’s tolerance setting (page 152), you can adjust their sensitivity by adjusting that setting in the Options bar. You also can run these commands more than once to get the selection you want. Figure 4-10: Top: Say you’re trying to select the red part of this Texas flag. After click- ing once with the Magic Wand (with a tolerance of 32), you still need to select a bit more of the red (left). Since the red pixels are all touching each other, you can run the Grow command a couple of times to make Photoshop expand your selection to include all the red (right). Bottom: If you want to select the red in these playing cards (what a poker hand!), the Grow command won’t help because the red pixels aren’t touching each other. In that case, click once with the Magic Wand to select one of the red areas (left) and then use the Similar command to grab the rest of them (right). Read ’em and weep, boys! The Color Range Command The Color Range command is similar to the tools in this section in that it makes selections based on colors, but it’s much better at selecting areas that contain lots of details (for example, the flower bunches in Figure 4-11). The Magic Wand tends to select whole pixels, whereas Color Range is more fine-tuned and tends to select more partial pixels than whole ones. This fine-tuning lets Color Range produce selections Photoshop CS5: The Missing Manual 154
  19. Selecting by Color with smoother edges (less blocky and jagged than the ones you get with the Magic Wand) and get in more tightly around areas with lots of details. As a bonus, you also get a handy preview in the Color Range dialog box, showing you which pixels it’ll select before you commit to the selection (unlike the Grow and Similar commands discussed on page 154). Figure 4-11: The Color Range command is handy when you need to select an area with a lot of details, like the red and blue petals of these flowers. The image in the dialog box’s preview area shows the part that Photoshop will select when you click the OK button. Up to Speed Selecting the Opposite After grabbing the sky, you can inverse (flip-flop) your You’ll often find it easier to select what you don’t want in selection to select the buildings instead. Simply choose order to get the selection you really do want. For example, Select➝Inverse or press Shift-⌘-I (Shift+Ctrl+I on a PC). look back at the photo of the Dallas skyline shown in Figure The lesson here is that it pays to spend a few moments 4-9 (page 152). If you want to select the buildings, it’s eas- studying the area you want to select and the area around ier to select the sky because its color is practically uniform. it. If the color of the surrounding area is uniform, reach for (It’d take you a lot longer to select the buildings because one of the tools described in this section and then inverse they’re irregularly shaped and vary so much in color.) your selection to save yourself tons of time! chapter 4: selections: choosing what to edit 155
  20. Selecting by Color Open the Color Range dialog box by choosing Select➝Color Range, either before or after you make a selection. If you already have a selection, Photoshop looks only at the pixels within the selected area, which is helpful if you want to isolate a certain area. For example, you could throw a quick selection around the red flower shown in the center of Figure 4-11 and use Color Range’s subtract from selection capabilities (explained later in this section) to carve out just the red petals. By contrast, if you want to use Color Range to help expand your selection, press and hold the Shift key while you choose Select➝Color Range. If you haven’t yet made a selection, Color Range examines your entire image. Use the Select pop-up menu at the top of the Color Range dialog box to tell Photo- shop which colors to include in your selection. The menu is automatically set to Sampled Colors, which lets you mouse over an image (your cursor turns into a tiny eyedropper; see Figure 4-11) and click the color you want to select. If you change the Select menu’s setting to Reds, Blues, Greens, or whatever, Color Range will examine your image and grab that range of colors all by itself—once you click OK. Note: As mentioned in the box on page 155, it’s sometimes easier to select what you don’t want in order to get the selection you need. The Color Range dialog box lets you select what you don’t want by turning on the Invert checkbox. If you’re trying to select adjacent pixels, turn on Localized Color Clusters. You can tweak the area Photoshop selects by adjusting the Fuzziness setting. Its factory set- ting is 40, but you can change this number to anything between 0 and 200. If you increase it, Photoshop includes more colors and makes larger selections. If you lower it, Photoshop creates a smaller selection because it gets pickier about matching col- ors. As you move the Fuzziness slider (or type a number in the text box), keep an eye on the dialog box’s preview area—all the parts of the image that Photoshop will include in your selection appear white (see Figure 4-11). Use the eyedroppers on the dialog box’s right side to add or subtract colors from your selection; the eyedropper with the tiny + sign adds to your selection and the one with the – sign subtracts from it. (Use the plain eyedropper to make your initial selection.) When you click one of the eyedroppers, mouse over to your image, and then click the color you want to add or subtract, Photoshop updates the Color Range dialog box’s preview area to show what the new selection looks like. It sometimes helps to keep the Fuzziness setting fairly low (around 50 or so) while you click re- peatedly with the eyedropper. Tip: You can use the radio buttons beneath the Color Range dialog box’s preview area to see either the selected area (which appears white) or the image itself. But there’s a better, faster way to switch between the two views: With Selection turned on, press the � key (Ctrl on a PC) to switch temporarily to Image preview. When you let go of the key, you’re back to Selection preview. Photoshop CS5: The Missing Manual 156
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