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Brush Size and Shape
Now that you have a feel for the basics of using the paint and edit tools, let's take a broader look at how you modify the performance of these tools. For example, every tool behaves differently according to the size and shape of your cursor, known as the brush tip. Different styles of brush tips are known as brush shapes, or just plain brushes (not to be confused with the brush tool, which folks sometimes call "the brush" as well). But while there's a lot of nomenclature at work here, the concept behind the brush shape is very simple. A big, round brush paints in broad strokes. A small, elliptical brush is useful for performing hairline adjustments. And if that's not enough — which it clearly isn't — you've a world of options in between and many more besides.
| Note | The settings and techniques I discuss in this section don't apply to the new color replacement tool. You can right-click (Control-click on the Mac) with the color replacement tool to access basic settings for brush shape, size, hardness, and even pressure-sensitivity. But, as I mentioned earlier, the many options in the Brushes palette are not available to the color replacement tool. |
Selecting a brush shape
Provided that a paint or edit tool (other than the color replacement tool) is active, there are a handful of ways to modify the brush shape in Photoshop CS:
Right-clicking: Right-click anywhere in the image window (Control-click on the Mac) to display a small palette of preset brush shapes, complete with a menu of additional options, as pictured in Figure 5-15. Scroll through the list of brush shapes, click the one you want to use, and then press Enter or Return to hide the palette. You can also press Escape to hide the palette and leave the brush shape unchanged.
Figure 5-15: The presets palette lets you select from a list of predefined brush shapes and load other ones from disk.
| Note | The presets palette previews how the brush looks both when you click and when you drag. If your computer includes a pressure-sensitive drawing tablet, or if you've adjusted the Fade parameter in the brush's Shape Dynamics settings (as I explain in the upcoming "Shape dynamics" section), the strokes appear to taper, as in the figure. Otherwise, they appear uniform. To dispense with the stroke previews, choose Large Thumbnail from the palette menu. To restore the stroke previews, choose Stroke Thumbnail. |
The Brushes palette: Choose Window Brushes or press F5 to display the Brushes palette, which appears on the left side of Figure 5-16. Click the words Brush Presets in the top-left corner of the palette to see a list of pre-defined brush shapes. You also get a large preview of the active brush shape at the bottom of the palette. Bear in mind, it will appear tapered only if you turn on the Shape Dynamics check box on the left side of the palette.
Figure 5-16: Two views of the Brushes palette, the fully expanded view (left) and the reduced view (right). The advantage of the latter is that it stacks well with Photoshop's other palettes.
The primary advantage of the Brushes palette is that you can define your own brush shapes and adjust various exciting dynamics, as I discuss in the next section. If all you want to do is select a predefined brush, right-clicking (or Control-clicking) is generally simpler.
| Tip | By default, the Brushes palette is wider than Photoshop's other palettes, which means it doesn't stack well on the right side of your screen. You have two ways of working around this. One is to get in the habit of pressing F5 to show or hide the palette at a moment's notice. The other is to turn off the Expanded View command in the Brushes palette menu, which lets you shrink the preset brush list to Photoshop's standard palettes width, as in the right example in Figure 5-16. |
Master diameter: With the preset palette or Brushes palette on screen, you can change the size of the brush by adjusting the Master Diameter value. Measured in pixels, this value represents the thickest stroke the brush will paint. (It can get thinner based on the Shape Dynamic settings, as I explain later in this chapter.) This means you're never locked into a preset brush diameter, even when painting with custom (nonround) brushes.
| Tip | Changing the brush diameter is so useful you can do it from the keyboard. Press the left bracket key, which looks like [, to make the brush smaller. Press the right bracket key, or ], to make the brush bigger. (Both keys are to the right of the P key on most keyboards.) Keep an eye on the brush icon in the Options bar to see how much smaller or larger the brush diameter gets. |
TipPreset shortcuts: You can cycle between presets even when no palette is visible. Press the comma key to toggle to the previous brush shape in the list. Press the period key to select the next brush shape. You also can press Shift-comma to select the first brush shape in the list (1-pixel wide) and Shift-period to select the last brush.
By default, your cursor outline reflects the active brush shape. If your cursor instead looks like a crosshair or tool icon, press Ctrl+K (z -K on the Mac) to bring up the Preferences dialog box, then press Ctrl+3 (z -3 on the Mac) for the Display & Cursors panel, and then select Brush Size from the Painting Cursors radio buttons. Now you can create a brush as big as 2,500 pixels in diameter and have your cursor grow accordingly.
| Tip | When you use a very small brush, four dots appear around the cursor perimeter, making the cursor easier to locate. If you need a little more help, press the Caps Lock key to access the more obvious crosshair cursor. |
Making your own brush shape
To create a custom brush shape, click the item named Brush Tip Shape in the Brushes palette, which displays the options shown in Figure 5-17. Photoshop displays thumbnails for the predefined brushes in the top-right quadrant of the palette. Select a brush to serve as a starting point for your custom creation, and then tweak away:
Figure 5-17: To change the size, shape, and hardness of a brush, click the item named Brush Tip Shape in the Brushes palette.
Diameter: This option determines the width of the brush. If the brush shape is elliptical instead of circular, the Diameter value determines the longest dimension. You can enter any value from 1 to 2,500 pixels.
| Photoshop | Flip X and Flip Y: New in Photoshop CS is the capability to flip a brush shape on either the x- or y-axis. Select the Flip X check box to flip the brush shape into a mirror image of itself. Select the Flip Y check box to flip the brush shape upside-down. These options are most obvious when you're using one of the more detailed brushes or a brush preset you've created from an image. |
Angle: This option pivots a brush shape on its axes. Unless the brush is elliptical, though, you won't see a difference. So it's best to first adjust the Roundness value and then adjust the Angle.
Roundness: Enter a Roundness value of less than 100 percent to create an elliptical brush shape. The value modifies the height of the brush as a percentage of the Diameter value, so a Roundness of 50 percent results in a short, fat brush.
| Tip | You can adjust the angle of the brush dynamically by dragging the gray arrow inside the box to the right of the Angle and Roundness options. Drag the handles on either side of the black circle to make the brush shape elliptical, as demonstrated in Figure 5-18. Drag the arrow tip to angle the brush. Or try this trick: Click anywhere in the white box to move the arrow to that point. |
Figure 5-18: Drag the black handles and gray arrow to change the roundness and angle of the brush, respectively. The Roundness and Angle values update automatically, as does the preview of the brushstroke at the bottom of the palette.
Hardness: Except when using the pencil tool, brushes are always antialiased. You can further soften the edges of a brush by dragging the Hardness slider bar away from 100 percent. The softest setting, 0 percent, gradually tapers the brush from a single solid-color pixel at its center to a ring of transparent pixels around the brush's perimeter. Figure 5-19 shows how low Hardness percentages expand the size of a 200-pixel brush beyond the Diameter value (as demonstrated by the examples in the bottom row). Even a 100-percent hard brush shape expands slightly because it is antialiased. The Hardness setting is ignored when you use the pencil tool.
Figure 5-19: A 200-pixel brush as it appears when set to each of four Hardness percentages. In the bottom row, I placed the brushes on a separate layer and applied a black fringe so you could see the effective diameter of each Hardness value.
| Tip | Like Diameter, Hardness is one of those settings that you need regular access to. So the ever-helpful Photoshop lets you change the Hardness from the keyboard. Press Shift-[ (Shift-left bracket) to make the brush softer; press Shift-] (Shift-right bracket) to make the brush harder. Both shortcuts work in 25-percent increments. For example, you have to press Shift-] four times to go from 0 percent Hardness to 100 percent. |
Spacing: In real life, a brush lays down a continuous coat of paint. But that's not how it works on the computer. Photoshop blasts out a stream of colored spots. The Spacing option controls how frequently the spots are emitted, measured as a percentage of the brush shape. For example, suppose the Diameter of a brush is 40 pixels and the Spacing is set to 25 percent (the default setting for all predefined brushes). For every 10 pixels (25 percent of 40) you drag with the brush tool, Photoshop lays down a 40-pixel wide spot of color. A Spacing of 1 percent provides the most coverage but also slows down the performance of the tool. If you deselect the Spacing check box, the effect of the tool is wholly dependent on the speed at which you drag; this can be useful for creating splotchy or oscillating lines. Figure 5-20 shows examples.
Figure 5-20: Examples of lines drawn with the brush tool subject to different Spacing values. Values greater than 100 percent are useful for creating dotted-line effects. The final line was created by turning off the Spacing option.
| Tip | In my experience, ridges generally begin to appear at the default Spacing value of 25 percent, especially when painting with a mouse. If you notice lumps in your brushstrokes, lower the Spacing to 15 percent (as illustrated in the second example in Figure 5-20), which ensures a good mix of speed and smoothness. When using a soft-edged brush, lower Spacing values result in a denser, fatter stroke, and higher values result in a lighter, thinner stroke. High Spacing values are great for creating dotted lines. |
After you edit a brush, you can save the brush for later use by clicking the tiny page icon at the bottom of the palette. Photoshop suggests a name, which you can then change. To save a brush without being asked to name it, Alt-click the page icon (or Option-click on the Mac). Photoshop stores the brush with your program preferences so that it's preserved between editing sessions.
| Caution | Note that if you delete the preferences file (as discussed in Chapter 2), you lose your custom brushes. To ensure that your custom brushes are saved in case you delete the preferences file or for use on another machine, choose Save Brushes from the palette menu. See the upcoming section "Saving and loading brush sets" for more information. |
To delete a brush from the list, switch back to the Brush Presets view and drag the brush to the trash icon at the bottom of the palette.
Defining a custom brush
Photoshop allows you to not only modify the size and roundness of a brush, but define a custom brush as well. Start by making a new image and doodling the shape of your brush tip. For now, any squiggle will do. Then use the rectangular marquee tool to select the doodle. (The rectangular marquee is discussed in "Geometric selection outlines" in Chapter 8). You don't have to be particularly careful; just select the general area around the doodle, as I did in Figure 5-21. Photoshop is smart enough to distinguish the confines of the brush from its background.
Figure 5-21: After selecting a doodle against a white background, choose Edit Define Brush and enter a name to turn the doodle into a custom brush.
Next, choose the Define Brush command from the Edit menu. Photoshop invites you to give your brush a name; if you're not feeling inspired, just press Enter or Return and accept the default name, Sampled Brush #1.
After you define a custom brush, you can tweak it just like any other brush inside the Brush Tip Shape panel of the Brushes palette. You can adjust the Diameter, Angle, and Roundness (height versus width) of your new brush. As shown in Figure 5-22, the only option that appears dimmed is Hardness; you have to accept the sharpness of the brush as it was originally defined. A custom brush will even grow and shrink according to stylus pressure.
Figure 5-22: Photoshop lets you modify the size, shape, and angle of a custom brush, all of which are accurately reflected by the brush cursor.
To restore a custom brush to its original size, click the Use Sample Size button in the Brush Tip Shape panel of the Brushes palette.
Saving and loading brush sets
After you define a handful of brushes — custom or otherwise — you may want to save them for use on a different computer or to avoid losing them in the event of a hard drive crash. Photoshop saves multiple brushes at a time to libraries. The program also ships with several predefined libraries, which you can find in the Presets/Brushes folder inside the folder that contains the Photoshop application. Brush libraries have the .abr file extension.You can save brush sets — as well as load and edit them — by choosing commands from the Brushes palette menu when the Brush Presets panel is displayed. Or choose commands from the presets palette that you get when right-clicking with a paint or edit tool (other than the color replacement tool). You can also manage libraries by choosing Edit Preset Manager. Figure 5-23 gives you a look at the Preset Manager with the Brushes panel at the forefront. If you're already working in the Preset Manager, press Ctrl+1 (z -1 on the Mac) to get to the Brushes panel.
Figure 5-23: Choose Edit Preset Manager to display the central headquarters for loading, saving, and editing brush sets.
By default, the Brushes palette displays a list of nearly 70 predefined brushes, including both elliptical and custom varieties. You can't delete this brush set, but you can prevent brushes you don't use from taking up space in the palette. You also can load or create a different set, combine two or more sets, and add or delete brushes from your custom brush sets. Here's the drill:
Save a brush set: To save all brushes currently displayed in the Brushes palette, choose Save Brushes from the palette menu. If you want to save only some of the brushes as a set, however, choose Edit Preset Manager. Shift-click the brushes you want to save and then click the Save Set button.Regardless of where you initiate the save, Photoshop takes you to the Save dialog box, where you can name your brush set. By default, brushes are saved in the Presets/Brushes folder, which is a darn good place for them. The next time you start Photoshop, your new brush set appears on the Brushes palette menu along with other available sets.
Use a different brush set: If you want to put the current brush set away and use a different set, choose Replace Brushes from the Brushes palette menu and select the brush set you want to use. Alternatively, click the arrowhead at the top of the scrolling list of icons in the Preset Manager dialog box to display a similar menu, and then choose Replace Brushes from that menu.
Load multiple brush sets: You can keep multiple brush sets active if you want. After loading the first set, choose Load Brushes from the Brushes palette menu or click the Load button in the Preset Manager dialog box. Photoshop appends the second brush set onto the first. If you want to keep using the two sets together, you may want to save them as a new, custom brush set.
Delete a brush: To delete a brush from the current brush set, select it from the Brush Presets panel of the Brushes palette and click the trash icon. Or choose Delete Brush from the palette menu.
| Tip | Want to give a bunch of brushes the boot? Do the job in the Preset Manager dialog box. Shift-click the brushes you no longer want and then click the Delete button. |
Restore default brushes: To return to the default Photoshop brush set, choose Reset Brushes from the menu in the palette or the dialog box. You then have the option of either replacing the existing brushes with the default brushes or simply adding them to the end of the palette.
Rename a brush: If you ever want to rename a brush, select it in the Preset Manager dialog box and click the Rename button. Or, even easier, double-click the brushstroke in the Brush Presets panel of the Brushes palette.
| Caution | If you want your new brush names to live in perpetuity, resave the brush set. Otherwise, the names will revert to their original labels when and if you replace the brush set. |
