Selecting Rectangles, Squares, Ellipses, and Circles

If you want to create a selection that’s rectangular or elliptical, you use — guess what — the Rectangular and Elliptical Marquee tools, respectively. The Rectangular and Elliptical Marquee tools are so easy to use that they make the lasso look complicated. You just drag from one corner to the opposite corner and release the mouse button. (Okay, ellipses don’t have corners, so you have to use your imagination a little bit.) The dotted marquee follows the movements of your cursor on-screen, keeping you apprised of the selection outline in progress.

But Photoshop has never been one to provide you with only one way to use a tool — or, in this case, two tools. For example, you can also use these tools to select perfect squares or circles.

Grabbing a square or circle

Every so often, you may feel the urge to apply some puritanical constraints to your selection outlines. Enough of this random width and height business — you want perfect squares and circles. Lucky for you, Photoshop obliges these fussbudget impulses by letting you constrain shapes selected with the Marquee tool.

To select a perfect square, press the Shift key after you begin dragging with the Rectangular Marquee tool. To draw a perfect circle, press Shift after you begin dragging with the Elliptical Marquee tool. For the best results, you should first begin dragging, press and hold Shift, drag to the desired location and release the mouse button, and finally release Shift. In other words, press Shift after you start the drag and hold it until after you complete the drag.

Warning

If you press Shift before dragging, you run the risk of adding to the previously selected area. Here’s the deal: If a portion of your image was selected before you started Shift+dragging, Photoshop sees to it that the area remains selected and selects the marqueed area as well. Meanwhile, the shape of the marquee is not constrained to a square or a circle. Befuddling, huh? If this happens to you, press Ctrl+Z (z+Z on a Mac) to undo the selection; then try again, taking care to press Shift during — not before — your drag.

Getting even more control over selections

Are you crazed for control? Do your tyrannical desires know no bounds? If so, you probably aren’t appeased by drawing a square or a circle. What you want is to apply even more stringent constraints.

Remember

Like the Lasso options discussed earlier in “Exploring your Lasso options,” the Marquee options I discuss in the following sections sport Anti-aliased and Feather options, which respectively soften the selection outline and make it blurry. However, the Anti-aliased check box is dimmed when you use the Rectangular, Single Column, and Single Row Marquee tools. Perpendicular edges never need softening because perpendicular edges can’t be jagged.

The Fixed Aspect Ratio option

Suppose that you’re the sort of pixel-oppressor who wants to select a rectangular or oval area that’s exactly twice as wide as it is tall. With your Marquee tool selected, choose the Fixed Aspect Ratio option from the Style pop-up menu on the Options bar. The Width and Height text boxes come to life, letting you specify an aspect ratio, which is a precise proportion between the width and height of a marquee. To make the marquee twice as wide as it is tall, enter 2 as the Width value. Then press Tab to highlight the Height value and enter 1.

The Single Row and Single Column options

You can set up the marquee to select a row or column of pixels that is a single pixel tall or wide. To do this, select the Single Row or Single Column icon from the Marquee flyout menu in the Toolbox. Then click to create the marquee. If you select Single Row, the marquee is 1 pixel tall and extends across the entire width of your image; if you select Single Column, the marquee is 1 pixel wide and as tall as your image. After you click to create the marquee, you can drag it to reposition it if necessary.

The Fixed Size option

To constrain the marquee to an exact size, select the Fixed Size option from the Style pop-up menu. Then enter the exact dimensions of your desired marquee into the Width and Height text boxes.