Use Add and Subtract Modes for Refining Selections

To make a good selection start by outlining the basic shape with the lasso tool. Then alternately press the Shift and Alt (Windows) / Shift and Option (Mac) keys to add or subtract from the selected area until it is perfect. The Shift key will add to your current selection; the Alt/Option key will subtract from it. You can also use the circle and rectangle selection tools and the magic wand as well as the lasso.

This method can really make a good selection. I often use it to select the background and then blur it making the subject seem even more sharp.

It is also useful for creating basic shapes. For instance, you can make a cresent shape by making a circle selection and then subtracting a smaller circle. Or make a half-circle by making a circle selection and subtracting half of it with the rectangle marquee tool. Or make those famous mouse ears by adding three circle shapes.

Related Resources:
• Photoshop Masks & Selections

Compatibility: Photoshop (any version), Photoshop Elements

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