To create a smooth selection in Photoshop* with one of the many selection tools, such as the Magic Wand tool, you must first select the ‘anti-aliased’ check box on the tool options bar. This tells Photoshop to pick up a few neighbouring pixels to create a gradational effect. The result is usually more appealing than the alternative hard-edged selection.

Sometimes, though, the stray pixels are radically different in colour, which becomes really obvious after you move or paste the selection on top of lighter or darker coloured pixels. When this happens, you may think the only solution is to manually delete the unwanted pixels with the Eraser tool. Luckily, Photoshop is intuitive enough to include the Matting Commands, which are designed to remedy this exact problem.

To defringe an anti-aliased selection filled with pure colour, follow these simple steps below:

  1. In your ‘Layers’ tab, select ‘Matting’ and click on ‘Defringe.’ This will open a dialog box.
  2. Enter a small pixel value in the ‘Width’ text box (1 or 2 pixels usually does it).
  3. Click OK.

To remove background colour from a selection is just as simple. In your ‘Layers’ tab, select ‘Matting’ and click on ‘Remove Black Matte’ or ‘Remove White Matte.’ Photoshop replaces the specified number of pixels along the selection’s edge with colour from neighbouring pixels in the selection. The result is a smooth selection without any discolouration along the edges.

*This tip only applies to Adobe Photoshop Cs2, Cs3, Cs4 and Cs5.