You can add an effect around a featured object that looks like a glowing halo that softly fades into the background. In addition to having aesthetic appeal, the effect described in this task works well when you're silhouetting an object against a white or dark background. It also works to separate the object from its background.
Open the File and Draw a Path
Choose File, Open and select the file you want to modify. Select the Pen tool from the toolbox. Use the techniques described in Part 3, "Selection Techniques," to draw a path around the desired object.
Select the Outside of the Object
Choose Window, Paths to open the Paths palette. With the path tile selected, choose Make Selection from the palette menu and click OK in the Make Selection dialog box that appears. Then choose Select, Inverse to deselect the object and select only the background.
Select the Glow Color
Double-click the Foreground color swatch in the toolbox; after the Color Picker opens, select a color for the glow. Click OK to close the Color Picker.
Select the Paintbrush tool in the toolbox. In the Options bar, drag the Pressure slider to about 8% or 10% percent and select a very large feathered brush. Click the Brush icon and set the Master Diameter slider for the brush size. Select the Airbrush icon in the Options bar and set the Flow and Opacity as desired.
Stroke the Path
With the new path selected in the Paths palette, select Stroke Path from the palette menu. In the Stroke Path dialog box that appears, click OK to apply the stroke using the brush settings specified in Step 4.
Modify Brush Settings
Restroke the path several times by repeating Steps 4 and 5. Each time you reapply the stroke, select a smaller brush size and increase the pressure. This intensifies the stroke as it gets close to the object, simulating the glow effect. Deselect the path in the Paths palette to view the effect unobscured by the path.
Hiding the Path
It can be hard to evaluate the effect of the stroke while the path is selected because the outline of the path obscures the image edge. After you apply each stroke, you may want to deselect the path in the Paths palette. After evaluating the stroke results, reselect the path (by clicking with one of the Pen tools) and continue building the effect.
Other Path-Creation Methods
You can also use any other method described in this book to create a selection. For example, you can use Quick Mask to paint a selection, or you can use the Magnetic Lasso tool. After you create the selection, you can easily transform it into a path by clicking the Make Work Path icon at the bottom of the Paths palette. You can then edit the path using any of the Pen tools from the toolbox.