Photoshop 6 for Windows Bible- P12 ppt

297 Chapter 7 ✦ Retouching, Repeating, and Restoring That one action —clicking on a state—is the gist of what you need to know to travel forward and backward through time in Photoshop. If that’s all you ever learn, you’ll find yourself working with greater speed, freedom, and security than is possible in virtually any other graphics application. But this represents only the first in a long list of the History palette’s capabilities. Here’s the rest of what you might want to know: ✦ Changing the number of undos: By default, Photoshop records the last 20 operations in the History palette. When you perform the 21st operation, the first state is shoved off the list. In Photoshop 6, you set the number of operations that the History palette tracks in the Preferences dialog box. Choose Edit ➪ Preferences ➪ General or press Ctrl+K to open the dialog box and enter the value you want to use in the History States box. If your computer is equipped with 32MB or less of RAM, you might want to lower the value to 5 or 10 to maintain greater efficiency. On the other hand, if you become a time-traveling freak (like me) and have plenty of RAM, turn it up, baby, all the way up! ✦ Undone states: When you revert to a state by clicking on it, every subsequent state turns gray to show that it’s been undone. You can redo a grayed state simply by clicking on it. But if you perform a new operation, all grayed states disappear. You have one opportunity to bring them back by pressing Ctrl+Z; if you perform another new operation, the once-grayed states are gone for good. ✦ Working with non-sequential states: If you don’t like the idea of losing your undone states — every state is sacred, after all — choose the History Options command and select the Allow Non-Linear History check box (see Figure 7-27). Undone states no longer drop off the list when you perform a new operation. They remain available on the off chance that you might want to revisit them. It’s like having multiple possible time trails. Figure 7-27: Choose the History Options command to permit Photoshop to record states out of order. The Allow Non-Linear History check box does not permit you to undo a single state without affecting the subsequent states. For example, let’s say you paint with the airbrush, smear with the smudge tool, and then clone with the rubber stamp. You can revert back to the airbrush state and then apply other opera- tions without losing the option of restoring the smudge and clone. But you can’t undo the smudge and leave the clone intact. Operations can only occur in the sequence they were applied. Note 6 Photoshop 6 298 Part II ✦ Painting and Retouching If you revert back to a state and then apply an edit, the reverted state and all actions that fall between that state and the new edit are set off by horizontal lines running across the palette. The lines show you which operations you’ll lose if you undo the first state in the group. ✦ Stepping through states: As I mentioned earlier, you can press -Ctrl+Alt+Z to undo the active step or Ctrl+Shift+Z to redo the next step in the list. Backstepping goes up the list of states in the History palette; forward stepping goes down. Keep in mind that if the Allow Non-Linear History check box is active, backstepping may take you to a state that was previously inactive. ✦ Flying through states: Drag the right-pointing active state marker (labeled in Figure 7-26) up and down the list to rewind and fast-forward, respectively, through time. If the screen image doesn’t appear to change as you fly by cer- tain states, it most likely means those states involve small brushstrokes or changes to selection outlines. Otherwise, the changes are quite apparent. ✦ Taking a snapshot: Every once in a while, a state comes along that’s so great, you don’t want it to fall by the wayside 20 operations from now. To set a state aside, choose New Snapshot or click the little page icon at the bottom of the History palette. By default, Photoshop no longer displays the New Snapshot dialog box asking you to name the snapshot. If you want to name a snapshot, Alt-click the New Snapshot icon. Or choose History Options from the palette menu and select the Show New Snapshot Dialog by Default option. Photoshop then presents the dialog box. In the dialog box, you also can specify whether you want to save all layers (as by default), flatten the image, or retain just the active layer. The new snapshot — as it’s called— then appears in the top portion of the palette. If you turn on the Show New Snapshot Dialog by Default check box, you can circumvent the dialog box by Alt-clicking the New Snapshot icon. (The state has to be active to convert it to a snapshot, so you can’t drag a state and drop it onto the page icon, as you can drag-and-drop elements in other palettes.) Photoshop lets you store as many snapshots as your computer’s RAM permits. Also worth noting, the program automatically creates a snapshot of the image as it appears when it’s first opened. If you don’t like this opening snapshot, you can turn it off inside the History Options dialog box. ✦ Creating a snapshot upon saving the image: Select the Automatically Create New Snapshot When Saving box in the History Options dialog box to create a new snapshot every time you save your image. ✦ Saving the state permanently: The problem with snapshots is that they last only as long as the current session. If you quit Photoshop or the program crashes, you lose the entire history list, snapshots included. To save a state so you can refer to it several days from now, choose the New Document command or click the leftmost icon at the bottom of the History palette. You can also drag and drop a state onto the icon. Either way, Photoshop duplicates the state to a new image window. Then you can save the state to the format of your choice. Tip 6 Photoshop 6 6 Photoshop 6 299 Chapter 7 ✦ Retouching, Repeating, and Restoring ✦ Setting the source: Click to the left of a state to identify it as the source state. The history brush icon appears where you click. The source state affects the performance of the history brush, art history brush, Fill command, and eraser, if you select Erase to History. The keystroke Ctrl+Alt+Backspace fills the selection with the source state. ✦ Trashing states: To delete any state and those that follow, drag the state to the trash icon at the bottom of the palette. Your image updates accordingly. If the Allow Non-Linear History check box is on, clicking the trash can deletes just the active state. If your machine is equipped with little RAM or you’re working on a particu- larly large image, Photoshop may slow down as the states accumulate. If it gets too slow, you may want to purge the History palette. You can clear every state from the active state forward without affecting the image by Alt-clicking Clear History in the palette menu. You can also choose Edit ➪ Purge ➪ Histories to purge the list of states for all open documents. You can’t undo either purge command. So if you want to clear the states from the palette but have the option of choosing Undo to bring them back, choose Clear History without Alt-clicking. Painting away the past The History palette represents the regimental way to revert images inside Photoshop. You can retreat, march forward, proceed in linear or non-linear formation, capture states, and retire them. Every state plays backward in the same way it played for- ward. It’s precise, predictable, and positively by the book. But what if you want to get free-form? What if you want to brush away the present and paint in the past? In that case, a palette isn’t going to do you any good. What you need is a pliable, emancipated, free-wheeling tool. As luck would have it, Photoshop offers five candidates — the eraser, magic eraser, background eraser, history brush, and art history brush. The eraser washes away pixels to reveal underlying pixels or exposed canvas. The magic eraser and back- ground eraser, both added in Version 5.5, erase a range of similarly colored pixels and background pixels, respectively. The history brush takes you back to a kinder, simpler state; the art history brush does the same but enables you to paint using special artistic effects. Although the functions of these tools overlap slightly, they each have a very specific purpose, as becomes clear in the following sections. As you work with any of these tools, remember that you can use the Edit➪ Fade com- mand (formerly on the Filter menu) to blend the altered pixels with the originals, just as you can when applying a filter. You can adjust both the opacity and blend mode of the erased or painted pixels. Chapter 10 explores the Fade command in detail. Cross- Reference Caution Tip 300 Part II ✦ Painting and Retouching The eraser tool When you work with the eraser, you can select from four eraser styles: Paintbrush, Airbrush, Pencil, and Block. Block is the old 16 × 16-pixel square eraser that’s great for hard-edged touch-ups. The other options work exactly like the tools for which they’re named. In earlier versions of Photoshop, pressing E cycled you through the eraser styles. That shortcut now cycles through the eraser, magic eraser, and background eraser, all of which share a flyout menu and keyboard shortcut ( E) in Version 6. You now must select the eraser style from the Mode pop-up menu on the Options bar, as shown in Figure 7-28 (press Enter with the eraser selected in the toolbox to display the bar). Figure 7-28: When the eraser is selected, the Mode pop-up menu offers a choice of eraser styles rather than the brush modes available for the painting tools. In addition to four styles, the Options bar provides the Brush palette, the Opacity control, and the Brush Dynamics palette, all of which work as described in Chap- ter 5. When the Paintbrush option is active, you even have access to the Wet Edges check box, also covered in Chapter 5. The only thing you can’t do is choose a brush mode (Normal, Overlay, Darken, Lighten, and so on)— although, as I mentioned a little while ago, you can apply the Fade command after the fact to fade and blend your eraser strokes. Although the eraser is pretty straightforward, there’s no sense in leaving any stone unturned. So here’s everything you ever wanted to know about the art of erasing: ✦ Erasing on a layer: When you’re working on the Background layer, the eraser merely paints in the background color. Big whoop. What distinguishes the eraser tool from the other brushes is layers. If you drag on a layer and dese- lect the Lock check boxes for transparency and image pixels in the Layers palette, the eraser tool removes paint and exposes portions of the underlying image. The eraser tool suddenly performs like a real eraser. 6 Photoshop 6 301 Chapter 7 ✦ Retouching, Repeating, and Restoring If you select the transparency Lock check box in the Layers palette, Photo- shop won’t let the eraser bore holes in the layer or alter areas that are already transparent. Instead, the eraser can paint opaque pixels with the background color. If you select the check box for locking image pixels, you can’t erase or paint any part of the layer. For more information on the check boxes in the Layers palette, read Chapter 12. ✦ Erasing lightly: Change the Opacity setting on the Options bar to make por- tions of a layer translucent in inverse proportion to the Opacity value. For example, if you set the Opacity to 90 percent, you remove 90 percent of the opacity from the layer and, therefore, leave 10 percent of the opacity behind. The result is a nearly transparent stroke through the layer. ✦ Erasing versus using layer masks: As described in the “Creating layer-specific masks” section of Chapter 12, you can also erase holes in a layer using a layer mask. But unlike the eraser —which eliminates pixels for good —a layer mask doesn’t do any permanent damage. On the other hand, using the eraser tool doesn’t increase the size of your image as much as a layer mask does. (You can argue that any operation — even a deletion —increases the size of the image in RAM because the History palette has to track it. But the eraser is still more memory-efficient than a layer mask.) So it’s a trade-off. ✦ Erasing with the pencil: When you work with the pencil tool and select the Auto Erase check box on the Options bar, you draw in the background color any time you click or drag a pixel colored in the foreground color. This tech- nique can be useful when you’re drawing a line against a plain background. Set the foreground color to the color of the line; set the background color to the color of the background. Then use the pencil tool to draw and erase the line until you get it just right. I use this feature all the time when preparing screen shots. Adobe engineers call the Auto Erase check box their “ode to Fatbits,” from the ancient MacPaint zoom function. Like the eraser, the pencil tool is affected by the Lock check boxes in the Layers palette. Unlike the eraser, the pencil always draws either in the fore- ground or background color, even when used on a layer. ✦ Erasing to history: Press Alt as you drag with the eraser to paint with the source state identified by the history brush icon in the History palette. (By default, Photoshop sets the source state to the image as it appeared when first opened.) It’s like scraping away the paint laid down by the operations fol- lowing the source state, as demonstrated quite graphically in Figure 7-29. Note Cross- Reference 302 Part II ✦ Painting and Retouching Figure 7-29: After making a dreadful mistake (left), I Alt-dragged with the eraser tool to restore the image to the way it looked in the source state (right). Alternatively, you can select the Erase to History check box on the Options bar. In this case, dragging with the eraser reverts and Alt-dragging paints in the background color. Many people use the term “magic eraser” to refer to the eraser set in revert mode. But Photoshop 5.5 introduced an official magic eraser, which erases background pixels instead of erasing to history. So be careful not to get the two confused. The magic eraser As I just mentioned, the magic eraser, found on the same flyout as the regular eraser, erases background pixels. Or, at least, that’s the idea. When used incor- rectly, the magic eraser wipes out any pixels that it touches. If you’re familiar with the magic wand, which I cover in Chapter 8, using the magic eraser is a cinch. The two tools operate virtually identically, except that the wand selects and the magic eraser erases. When you click a pixel with the magic eraser, Photoshop identifies a range of simi- larly colored pixels, just as it does with the magic wand. But instead of selecting the pixels, the magic eraser makes them transparent, as demonstrated in Figure 7-30. Bear in mind that in Photoshop, transparency requires a separate layer. So if the image is flat (without layers), Photoshop automatically floats the image to a sepa- rate layer with nothing underneath. Hence the checkerboard pattern shown in the second example in the figure— transparency with nothing underneath. Note 303 Chapter 7 ✦ Retouching, Repeating, and Restoring Figure 7-30: To delete a homogeneously colored background, such as the sky in this picture, click inside it with the magic eraser (bottom). The Lock check boxes in the Layers palette affect the magic eraser. When you have no check boxes selected, the magic eraser works as I just described it. But if you lock transparent pixels, the magic eraser paints opaque pixels in the background color and leaves transparent areas untouched. You can’t use the magic eraser at all on a layer for which you’ve locked image pixels. 6 Photoshop 6 304 Part II ✦ Painting and Retouching You can further alter the performance of the magic eraser through the controls on the Options bar, as described in the following list. Except for the Opacity value, these options work the same way for both the magic eraser and magic wand: ✦ Opacity: Lower this value to make the erased pixels translucent instead of transparent. Low values result in more subtle effects than high ones. ✦ Use All Layers: When turned on, this check box tells Photoshop to factor in all visible layers when erasing pixels. The tool continues to erase pixels on the active layer only, but it erases them according to colors found across all layers. ✦ Anti-aliased: To create a soft fringe around the outline of your transparent area, leave this option turned on. If you’d prefer a hard edge— as when using a very low Tolerance value, for example — turn this check box off. ✦ Contiguous: Select this final check box, and the magic eraser deletes contigu- ous colors only— that is, similar colors that touch each other. If you prefer to delete all pixels of a certain color —such as the blue pixels in Figure 7-30 that are divided from the rest of the sky by the lion— turn the Contiguous check box off. The more magical background eraser The magic eraser is as simple to use as a hammer, and every bit as indelicate. It pounds away pixels, but it leaves lots of color fringes and shredded edges in its wake. You might as well select an area with the magic wand and press Backspace. The effect is the same. The more capable, more scrupulous tool is the background eraser. As demon- strated in Figure 7-31, the background eraser deletes background pixels as you drag over them. (Again, if the image is flat, Photoshop floats the image to a new layer to accommodate the transparency.) The tool is intelligent enough to erase background pixels and retain foreground pixels provided that — and here’s the clincher — you keep the cross in the center of the eraser cursor squarely centered on a back- ground-color pixel. Move the cross over a foreground pixel, and the background eraser deletes foreground pixels as well. As Figure 7-32 demonstrates, it’s the posi- tion of the cross that counts. As is the case when you work with the magic eraser, the Lock check boxes in the Layers palette affect the background eraser. In this case, locking image pixels pre- vents you from using the background eraser. Be aware that if you drag over a selec- tion that’s already partially transparent, locking transparent pixels does not protect the selection from the background eraser. 6 Photoshop 6 305 Chapter 7 ✦ Retouching, Repeating, and Restoring Figure 7-31: Drag around the edge of an image with the background eraser to erase the background but leave the foreground intact. You can select a brush for the background eraser in the Brush drop-down palette on the Options bar. In Photoshop 6, you can press the arrow keys to move from one brush icon to another in the palette. Pressing the bracket keys, [ and ], lowers and raises the brush size — by 10 pixels for brushes smaller than 100 pixels in diameter, by 25 pixels for brushes from 100 pixels to 199 pixels in diameter, and by 50 pixels for brushes 200 pixels and larger. If you simply want to switch from a hard brush to a soft one, press Shift-left bracket; press Shift-right bracket to go from a soft brush to a hard one. You can also modify the performance of the background eraser using the Options bar controls, pictured in Figure 7-33. These options are a bit intimidating at first, but they’re actually pretty easy to use: ✦ Limits: Choose Contiguous from this pop-up menu, and the background eraser deletes colors inside the cursor as long as they are contiguous with the color immediately under the cross. To erase all similarly colored pixels, whether contiguous or not, select Discontiguous. One additional option, Find Edges, searches for edges as you brush and emphasizes them. Although interesting, Find Edges has a habit of producing halos and is rarely useful. ✦ Tolerance: Raise the Tolerance value to erase more colors at a time; lower the value to erase fewer colors. Low Tolerance values are useful for erasing around tight and delicate details, such as hair. 6 Photoshop 6 306 Part II ✦ Painting and Retouching Figure 7-32: Keep the cross of the background eraser cursor over the background you want to erase (top). If you inadvertently move the cross over the foreground, the foreground gets erased (bottom). [...]... and deleting points You can even transfer a path by dragging and dropping between Photoshop, Illustrator, and FreeHand For a discussion of the pen tool, read the “How to Draw and Edit Paths” section later in this chapter Photoshop 6 In Photoshop 6, selecting the Magnetic check box on the Options bar transforms the freeform pen into the magnetic pen, which used to be a tool in its own right The magnetic... still for a few moments, Photoshop decides it must be on target and anchors it down with a point If you want Photoshop to anchor points more frequently, raise the value For less frequent anchoring, lower the option High values tend to be better for rough edges; lower values are better for smooth edges Chapter 8 ✦ Selections and Paths ✦ Edge Contrast: This is the simplest of the options It tells Photoshop. .. items that you want Photoshop to display at all times As for creating selections, you have at your disposal a plethora of tools, all shown in Figure 8-2 and described briefly in the following list You can access most of the tools by using keyboard shortcuts, which appear in parentheses Chapter 8 ✦ Selections and Paths Photoshop Figure 8-2: Photoshop 6 offers a bounty of selection tools 6 When multiple... point and then move your mouse and watch Photoshop create the other points automatically It’s not a great tool, but it can prove handy when selecting image elements that stand out very clearly from their backgrounds Photoshop ✦ Freeform pen and magnetic pen (P): If you hate setting points but you need to create a clipping path, the freeform pen is the tool for you You just drag with the tool as if... rectangular marquee because antialiasing is always on for this tool.) 6 Photoshop novices often misunderstand the rectangular and elliptical marquee tools and expect them to create filled and stroked shapes In the past, the program offered no tools for creating such shapes — you had to draw a geometric marquee and then fill or stroke the selection Now Photoshop provides the shape tools, which can create... Factor It determines how close to an edge you have to move the cursor for Photoshop to accurately see the image element Large values are great for smooth elements that stand out clearly from their backgrounds If I raise the Width to 20 when selecting the top of the skull, for example, I can move the cursor 20 pixels away from the skull and Photoshop still shrinks the selection tight around the skull’s edge... selection outlines New ways to use Photoshop s pen tools Transforming selection outlines and paths independently of the image Painting along an open path Creating, saving, and exporting clipping paths ✦ ✦ ✦ ✦ 3 16 Part III ✦ Selections, Masks, and Filters How selections work Before you can edit a portion of an image, you must first select it, which is computerese for indicating the boundaries of the... Image Size dialog box Photoshop ✦ Sizing the marquee numerically: If you’re editing a screen shot or some other form of regular or schematic image, you may find it helpful to specify the size of the marquee numerically To do so, select Fixed Size from the Style pop-up menu and enter size values in the Width and Height option boxes To match the selection to a 64 0 × 480-pixel screen, for example, change... option box is available when you use either marquee tool To feather a selection is to blur its edges beyond the automatic antialiasing afforded by most tools For more information on feathering, refer to the “Softening selection outlines” section later in this chapter Photoshop ✦ Creating jagged ellipses: By default, elliptical selection outlines are antialiased If you don’t want antialiasing — you might... results in random coloring (true to the impressionist tradition) but slows down the brush’s response Photoshop ✦ Area: This value defines the area covered by a single dollop of paint Larger values generally mean more strokes are laid down at a time; reduce the value for a more sparse look 6 Spacing: This option, formerly known as the Tolerance value, limits where the art history brush can paint A value of . onto the icon. Either way, Photoshop duplicates the state to a new image window. Then you can save the state to the format of your choice. Tip 6 Photoshop 6 6 Photoshop 6 299 Chapter 7 ✦ Retouching,. create the path. To find out more about working with these tools, visit Chapter 14. 6 Photoshop 6 6 Photoshop 6 . the magic eraser at all on a layer for which you’ve locked image pixels. 6 Photoshop 6 304 Part II ✦ Painting and Retouching You can further alter the performance of the magic eraser through