Adobe Photoshop CS5 for Photographers - Martin Evening [19]
Figure 1.46 These composite screen shots show Quick Mask views of selections created by dragging out from the center with held down (top), with held down (middle) and (bottom).
After you have created an initial selection the modifier keys will behave differently. In Figure 1.48 you can see how if you hold down the key as you drag with the marquee or lasso tool, this adds to the selection (holding down the key and clicking with the magic wand tool also adds to an existing selection). If you hold down the key as you drag with the marquee or lasso tool, this subtracts from an existing selection (as does holding down the key and clicking with the magic wand tool). And the combination of holding down the keys together whilst dragging with a selection tool (or clicking with the magic wand) will create an intersection of the two selections. As well as using the above shortcuts, you will find there are also equivalent selection mode options in the Options bar for the marquee and lasso selection tools (see Figure 1.49).
Figure 1.48 These composite screen shots show examples of selections that have been modified after the initial selection stage. The top view shows an elliptical selection combined with a rectangular selection with held down, adding to a selection. The middle view shows an elliptical selection combined with a rectangular selection with held down, which subtracts from the original selection. The bottom view shows an elliptical selection combined with a rectangular selection with held down, which results in an intersected selection.
Figure 1.49 The Options bar has four modes of operation for each of the selection tools: Normal; Add to Selection; Subtract from Selection; and Intersect Selection. These are equivalent to the use of the modifier modes described in the main text when the tool is in Normal mode.
Modifier keys can also be used to modify the options that are available elsewhere in Photoshop. For example, if you hold down the key as you click on, say, the marquee tool in the Tools panel, you will notice how this allows you to cycle through all the tools that are available in this group. Whenever you have a Photoshop dialog box it is also worth exploring what happens to the dialog buttons when you hold down the key. You will often see the button names change to reveal more options. Typically, the Cancel button changes to say ‘Reset’ when you hold down the key.
Painting tools
The next set of tools we'll focus on are the painting tools, which include: the brush, pencil, mixer brush, blur, sharpen, smudge, burn, dodge and sponge tools. These can be used to paint, or to edit the existing pixel information in an image. If you want to keep your options open, you will usually find it is preferable to carry out your paint work on a separate new layer. This allows you to preserve all of the original image on a base layer and you can easily undo all your paint work by turning off the visibility of the paint layer.
The new round brush presets
As mentioned in the main text, there are now just six round brush presets. These allow you to select hard or soft brushes with either no pressure-linked controls, the brush size linked to the amount of pressure applied, or brush opacity linked to the amount of pressure applied.
When you select any of the painting tools, the first thing you will want to do is to choose a brush, which you can do by going to the Brush Preset Picker (the second item from the left in the Options bar) and select a brush from the drop-down list shown in Figure 1.50. Here you can choose from the many different types of brushes, including the bristle shape brushes that are new to Photoshop CS5. The Size slider can be used to adjust the brush size from a single pixel to a 2500 pixel-wide brush and, if one of the standard