Adobe Photoshop CS5 : Intermediate Selection Techniques (part 4) - Refine Edge Command

4. Refine Edge Command

Even though the Select menu offers several options, there is always room for improvement. Photoshop provides a powerful option for refining an existing selection—the Refine Edge command, which can be accessed in two ways. It is available in the Options bar for all selection tools. You can also access it by choosing Select > Refine Edge. This command is very intuitive, and its sliders provide quick feedback as you refine a selection. Let’s try it out:

1.	Open the file Ch05_Refine Edge.tif .
2.	Make an initial selection using a tool of your choice (the Quick Selection tool works well).
3.	Click the Refine Edge button in the Options bar. A new dialog box opens with additional controls.
4.	Click the View button to change the viewing mode for how the selection is displayed (or use the corresponding keyboard shortcut). Try the different modes to see the results: Tip: Change Your Refined View To cycle through the different viewing modes in the Refine Edge dialog box, just press the F key repeatedly. If you’d like to temporarily disable the view, press the X key. Marching Ants (M). Shows the selection with the started dashed line. Overlay (V). Behaves similarly to the Quick Mask mode. On Black (B). Previews the layer over black, which is good for light edges. On White (W). Shows the selected region over a white background. Black & White (K). Simulates a channel view where the selection displays as a black (transparent) and white (opaque) layer (with gray indicating partial transparency). On Layers (L). Composites the image over any other layers (or transparency if single-layer image). Reveal Layer (R). Shows the entire, original layer contents.
5.	Next you can use Edge Detection to clean up the edges further. These controls work best for areas of partial transparency. For this image, try to clean up some of the dark fringe and any of the holes in the skull that should be partially see-through: Tip: Smarter Refinements You can select the Show Radius or Show Original check box to make it easier to see the changes created with the Edge Detection options. Radius. Drag to refine the selection edge. Try a value of 8 for this image. Smart Radius. This option automatically evaluates contrast in the edges and attempts to correct for better transitions. If your object lacks uniform hardness and softness, use this option. Select this option for this image (and in most cases). Refine Radius tool. Use this brush-style tool to paint over any edges that need additional refinement. You can also hold the Option (Alt) key to switch to an erase mode to undo any unwanted refinements. Paint over the left edge of the skull.
6.	The next group of sliders allows you to adjust the edge globally. Experiment with the following sliders: Smooth. Removes any jagged edges. Feather. Softens the edge of the selection. Contrast. Increases the contrast of a selection’s edge. You’ll get better results in most cases with the Smart Radius and refinement tools. Shift Edge. Grows or shrinks a selection. This is a quick way to tighten a rough selection and remove color spill.
7.	The last category, output, determines how the processed selection is treated. Decontaminate Colors. Applies color correction to remove any color spill from the background onto the selected object.
8.	Finally, you’ll need to determine what Photoshop does with the new selection. The choices are many (and useful): Selection. Creates an active selection. Layer Mask. Creates a nondestructive mask that produces transparency in the highlighted layer. New Layer. Creates a new layer with only the selected area. New Layer with Layer Mask. Creates a new layer with only the selected area masked. This is the most flexible option. Choose this option for this document. New Document. Creates a new document with only the selected area. New Document with Layer Mask. Creates a new document with the selected area masked.
9.	Click OK to create the selection and masked image.