Undoing Actions in Adobe Photoshop CS5
Note: This excerpt does not include the lesson files. The lesson files are available with purchase of the book.
In a perfect world, you’d never make a mistake. You’d never click the wrong object. You’d always perfectly anticipate how specific actions would bring your design ideas to life exactly as you imagined them. You’d never have to backtrack.
For the real world, Photoshop gives you the power to step back and undo actions so that you can try other options. The next project provides you with an opportunity to experiment freely, knowing that you can reverse the process.
This project also introduces you to layering, which is one of the fundamental and most powerful features in Photoshop. Photoshop features many kinds of layers, some of which contain images, text, or solid colors, and others that simply interact with layers below them. The file for this next project has both kinds of layers. You don’t have to understand layers to complete this project successfully, so don’t worry about that right now. You’ll learn more about layers in Lesson 4, “Layer Basics,” and Lesson 9, “Advanced Layering.”
Undoing a single action
Even beginning computer users quickly come to appreciate the familiar Undo command. Once again, you’ll begin this project by looking at the final result.
- Click the Launch Bridge button (), and navigate to the Lesson01 folder.
- Select the 01C_End.psd file, press Shift, and select the 01C_Start.psd file. Both files appear in the Preview panel. In the start file, the tie is solid; in the end file, it is patterned.
- In the Content panel, deselect the 01C_End.psd file thumbnail, and then double-click the 01C_Start.psd file thumbnail to open it in Photoshop.
- In the Layers panel, select the Tie Designs layer.
Notice the listings in the Layers panel. The Tie Designs layer is a clipping mask. A clipping mask works somewhat like a selection in that it restricts the area of the image that can be altered. With the clipping mask in place, you can paint a design over the tie without worrying about any stray brush strokes disturbing the rest of the image. You’ve selected the Tie Designs layer because it’s the layer you’ll be editing now.
- In the Tools panel, select the Brush tool (), or press B to select it by its keyboard shortcut.
- In the options bar, click the brush size to display brush options. Then, move the Size slider to 65 pixels. In the list of
brushes, select the Soft Round Pressure Size brush. (The name will appear as a tool tip if you hover the pointer over a brush.)
If you want to try a different brush, that’s OK, but select a brush that’s reasonably close to 65 pixels—preferably between 45 and 75 pixels.
- Move the pointer over the image so that it appears as a circle the same diameter as the brush. Then draw a stripe anywhere
in the orange tie. You don’t have to worry about staying within the lines, because the brush won’t paint anything outside
the tie clipping mask.
Oops! Your stripe may be very nice, but the design calls for dots, so you’ll need to remove that stripe you just painted.
- Choose Edit > Undo Brush Tool, or press Ctrl+Z (Windows) or Command+Z (Mac OS) to undo the Brush tool action.
The tie is again a solid orange color, with no stripe.
Undoing multiple actions
The Undo command reverses only one step. This is a practicality, because Photoshop files can be very large, and maintaining multiple Undo steps can tie up a lot of memory, which tends to degrade performance. You could use the Step Backward command to undo additional steps one at a time. However, it’s faster and easier to step back through multiple actions using the History panel.
- Using the same Brush tool settings, click once over the (unstriped) orange tie to create a soft dot.
- Click several more times in different areas on the tie to create a pattern of dots.
- Choose Window > History to open the History panel. Then drag a corner of the History panel to resize it so that you can see
The History panel records the recent actions you’ve performed in the image. The current state is selected, at the bottom of the list.
- Click an earlier action in the History panel, and notice how the image changes. Several previous actions are undone.
- In the image window, create a new dot on the tie with the Brush tool.
Notice that the History panel has removed the dimmed actions that were listed after the selected history state and has added a new one.
- Choose Edit > Undo Brush Tool or press Ctrl+Z (Windows) or Command+Z (Mac OS) to undo the dot you created in step 5.
Now the History panel restores the earlier listing of dimmed actions.
- Select the state at the bottom of the History panel list.
The image is restored to the condition it was in when you finished step 2 of this exercise.
By default, the Photoshop History panel retains only the last 20 actions. This is a compromise, striking a balance between flexibility and performance. You can change the number of levels in the History panel by choosing Edit > Preferences > Performance (Windows) or Photoshop > Preferences > Performance (Mac OS) and entering a different value for History States.
Using a context menu
Context menus are short menus that contain commands and options appropriate to specific elements in the work area. They are sometimes referred to as “right-click” or “shortcut” menus. Usually, the commands on a context menu are also available in some other area of the user interface, but using the context menu can save time.
- If the Brush tool () is not still selected in the Tools panel, select it now.
- In the image window, right-click (Windows) or Control-click (Mac OS) anywhere in the image to open the Brush tool context
Context menus vary with their context, of course, so what appears can be a menu of commands or a panel-like set of options, which is what happens in this case.
- Select a finer brush, such as the Hard Round brush, and change the size to 9 pixels. You may need to scroll up or down the list in the context menu to find the right brush.
- In the image window, use the selected brush to create smaller dots on the tie.