When you extract an object, Photoshop erases its background to transparency. Pixels on the edge of the object lose the color components derived from the background, so they can blend with a new background without producing a color halo.
For superior results and nondestructive processing, use the Select > Refine Edge command. See Refine selection edges for instructions and links to additional helpful tutorials.
The Refine Edge command is particularly impressive with highly complex edge content such as wispy hair. Unlike the older Extract plug-in, which permanently erases pixel data, the Refine Edge command creates selection masks that you can later readjust and fine-tune.
The Extract plug-in is not available for Mac OS because it is incompatible with recent versions of that operating system, and the Refine Edge command produces better extractions.
In the Layers palette, select the layer containing the object you want to extract. If you select a background layer, it becomes a normal layer after the extraction. If the layer contains a selection, the extraction erases the background only in the selected area.
To avoid losing the original image information, duplicate the layer or make a snapshot of the original image state.
Enter a value, or drag the slider to specify the width of the Edge Highlighter tool . You also use the Brush Size option to specify the width of the Eraser, Cleanup, and Edge Touchup tools.
Choose a preset color option for the highlight that appears around objects when you use the Edge Highlighter tool, or choose Other to pick a custom color for the highlight.
Choose a preset color option, or choose Other to pick a custom color for the area covered by the Fill tool.
Select this option if you are highlighting a well-defined edge. The option helps you keep the highlight on the edge, and applies a highlight that is just wide enough to cover the edge, regardless of the current brush size.
If you use Smart Highlighting to mark an object edge that’s near another edge, decrease the brush size if conflicting edges pull the highlight off the object edge. If the object edge has a uniform color on one side and high-contrast edges on the other side, keep the object edge within the brush area but center the brush on the uniform color.
Select this option if the foreground or background of your image contains a lot of texture.
Enter a value or drag the slider to increase or decrease the smoothness of the outline. It’s usually best to begin with zero or a small value to avoid unwanted blurring of details. If there are sharp artifacts in the extraction result, you can increase the Smooth value to help remove them in the next extraction.
Choose the alpha channel from the Channel menu to base the highlight on a selection saved in an alpha channel. The alpha channel should be based on a selection from the edge boundary. If you modify a highlight based on a channel, the channel name in the menu changes to Custom. Your image must have an alpha channel for the Channel option to be available.
Select the Edge Highlighter tool , and draw to define the edge of the object you want to extract. Drag so that the highlight slightly overlaps both the foreground object and its background. Use a large brush to cover wispy, intricate edges where the foreground blends into the background, as with hair or trees.
Use either the Zoom tool or the Hand tool to adjust the view as needed.
If you need to erase the highlight, select the Eraser tool , and drag it over the highlight. To erase the entire highlight, press Alt+Backspace (Windows) or Option+Delete (Mac OS).
If the object has a well-defined interior, make sure the highlight forms a complete enclosure. You do not need to highlight areas where the object touches the image boundaries. If the object lacks a clear interior, highlight the entire object.
You can’t highlight the entire object if you’ve selected Textured Image or Force Foreground.
If the object has a well-defined interior, select the Fill tool . Click inside the object to fill its interior. Clicking a filled area again with the Fill tool removes the fill.
If you’ve selected Force Foreground, select the Eyedropper tool , and click inside the object to sample the foreground color, or click in the Color text box and use a Color Picker to select the foreground color. This technique works best with objects that contain tones of a single color.
Choose new Highlight and Fill options and draw again with the Edge Highlighter tool. Define the foreground area once more, and then preview the extracted object.
Specify new Extraction settings (Smooth, Force Foreground, or Color) and then preview the extracted object.
To erase background traces in the extracted area, use the Cleanup tool . The tool subtracts opacity and has a cumulative effect. You can also use the Cleanup tool to fill gaps in the extracted object. Hold down Alt (Windows) or Option (Mac OS) while dragging to add back opacity.
To edit the edge of the extracted object, use the Edge Touchup tool . The tool sharpens edges and has a cumulative effect. If there is no clear edge, the Edge Touchup tool adds opacity to the object or subtracts opacity from the background.
You can also clean up the image after an extraction by using the Background Eraser and History Brush tools in the toolbox.
After an extraction, you can add opacity back to the background and create other effects by choosing Edit > Fade Extract.