Waving the Magic Wand Tool

Sometimes you want to select an area so uniform in appearance that you want to simply tell Paint Shop Pro, "Go select that red balloon" or whatever it is. To you, with your human perception, the area is an obvious thing of some sort. In software, anything that even slightly mimics human perception is often called magic. The Magic Wand selection tool is no exception. It can identify and select areas of uniform color or brightness, somewhat as your eye does.

One benefit of this tool is that you can select areas with complex edges that would be a pain in the wrist to trace with the Freehand tool. For instance, a selection of blue sky that includes a complex skyline of buildings and trees would be relatively easy with the Magic Wand tool.

The Magic Wand tool doesn't, however, work as well as your eye. In particular, if the color or brightness of the area you're trying to select isn't uniform or doesn't contrast strongly with the surroundings, the selection is likely to be spotty or incomplete or have rough edges.

Making the selection

To make a selection, select the Magic Wand from the Selection toolset. Your cursor takes on the Magic Wand icon. Click the Magic Wand cursor on your image, and it selects all adjacent pixels that match (or nearly match) the pixel you clicked. (Note that the selection does not include isolated pixels — pixels that, even though they match, are separated from the place you clicked by nonmatching pixels.)

To get the selection you want when you use the Magic Wand tool, consult the Tool Options palette. It lets you define (by using the Match mode list) exactly what you mean by match and lets you adjust (by adjusting the Tolerance setting) how closely the selected pixels should match the one you clicked.

If your image uses layers, be sure that the active layer is the one containing the area you want to select. Enable the Sample Merged check box on the Tool Options palette so that the Magic Wand tool examines all layers combined. Otherwise, the Magic Wand tool selects a totally wrong area, and you wonder what's happening!

Choosing Match mode for better results

Click the Match Mode list box and you can choose exactly how you want Paint Shop Pro to select the pixels around the place you clicked.

Some of the choices are shown in this list:

  • RGB Value: When you choose this option, you tell Paint Shop Pro to "select pixels that match in both color and brightness." Clicking a red apple using this choice may select only the highlighted side where you clicked, for instance. Technically, it selects all adjacent pixels with red (R), green (G), and blue (B) primary color values that match the one you clicked.
  • Hue: You're telling Paint Shop Pro to "select pixels that match in color" when you choose Hue. Hue, however, is somewhat more independent of brightness than the RGB value. Clicking on a red apple with this choice is more likely to select the entire apple than if you chose RGB Value. Technically, it selects all adjacent pixels with hues (in the Hue/Saturation/Lightness color system, or color wheel) that match the hue of the pixel you clicked.
  • Brightness: Brightness disregards color and selects all adjacent pixels whose brightness matches the one you clicked. This choice is useful for selecting things that are similarly illuminated, like shadows and highlights, or that are in a notably light or dark color compared with the background.
  • Opacity: Opacity, if you're not paying attention, is a measure of how transparent your image is. Opacity mode selects anything that's suitably close to the transparency of the selected pixel.
    Opacity is useful only when you're working on layers or images with transparent backgrounds. Even though you can technically paint a low- opacity streak over a white background using the Brush tool, the Magic Wand sees that even though the paint is ghostly and transparent, the background is 100 percent opaque. It then counts the background as part of the selection and goes on to select the entire image.
  • All Opaque: This option is a special choice for when you're working on an image that has transparent areas — areas of no content whatever — usually displayed with a checkered background. It tells Paint Shop Pro to select the area that has content around the pixel where you clicked. For instance, you may have photos of various air freshener products on a transparent layer, artistically floating over a cow pasture in the background. With this choice, you can just click one of the products to select it in its entirety.

Experiment to get the mode that works best for you! Press Ctrl+D to deselect each failed experiment, change match modes, and click again with the Magic Wand tool.

Setting tolerance to include more or fewer pixels

The Tolerance setting on the Tool Options palette helps you determine how much of an area is selected by the Magic Wand tool. You may have to undo your selection with Ctrl+D, adjust the tolerance, and click again with the Magic Wand tool several times to get the best selection possible.

Tolerance tells Paint Shop Pro how closely the pixels it selects should match the pixel you clicked — in RGB value, hue, or brightness, depending on which match mode you chose. (Tolerance doesn't matter for All Pixels match mode. A pixel either has content or it doesn't.) Here's how it works:

  • Lower the tolerance value to make a less extensive selection the next time you click.
  • Raise the tolerance value to make a more extensive selection the next time you click.

In Paint Shop Pro, low tolerance means that the Magic Wand tool tolerates little variation in color or brightness from the pixel you clicked. The tolerance value itself has no particular meaning; it's just a number.

The Tolerance value box on the Magic Wand tool's Tool Options palette has a clever adjustment feature you find in similar boxes throughout Paint Shop Pro. As with these types of boxes in any Windows program, you can type a value (from 0 to 200) in its text box or click its up or down arrow to adjust the value. We find that the best way is to click the down arrow, or Clever adjustment feature, and hold your mouse button down. A tiny slider appears that you can drag left or right to set the tolerance value lower or higher.

Tolerance can be a sensitive and picky adjustment. A small change can sometimes make a big difference in what gets selected. Unless you're trying to select an area well differentiated by color, brightness, or content, you probably have to adjust your selected area afterward.

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