Photoshop Masking- Advanced ( Part 1 )

One of the most difficult tasks in Photoshop is trying to select an object and remove it from its background to create a seamless composite. This tip and technique discusses some of the many ways to accomplish this using a variety of tools, shortcuts, and workarounds. It begins with the basic selection tools and shortcuts that extend their usage and then moves more in depth working with channels, the Background Eraser, Extract, the advanced blending option and the Pen tool. In order to achieve the professional results you need, two skills must be mastered - selecting and masking. They go hand in hand, and when used together are a formidable force.

The two easiest shapes to select in Photoshop are rectangles and ellipses. Using the rectangular or elliptical marquee tool, click and drag around the selection. Shortcuts: To constrain the selection to a square or circle, use the shift key. To draw the selection from the center use the Option (Mac)/Alt (Win). To reposition the orgin of the marquee while making a selection, use the spacebar.

Most of the time, the objects being selected with the rectangular and elliptical marquee tools are not shot straight on so the selection will need some adjusting. After drawing the selection, choose Select > Transform Selection to make changes to the selection area itself rather than the image data. To apply the transformation, click the check icon in the options bar. To cancel, click the X icon. Use the options bar to make numeric transformation. Shortcut: choose Select > Transform Selection and use: Cmd (Mac)/Ctrl (Win) to distort, Cmd Option (Mac)/Ctrl Alt (Win) to skew, Cmd Option Shift (Mac) /Ctrl Alt shift (Win) to change perspective.

Selecting odd shaped objects can be easily accomplished by using one of the Lasso tools and tracing around them. The regular lasso tool follows the path of your mouse where as the Polygonal Lasso tools will draw straight lines between mouse clicks. Hold the option (Mac)/Alt (Win) key to toggle between the lasso tools allowing you the best of free style drawing and straight line selections. The Magnetic Lasso tool will draw the selection based on the edge contrast between the subject and the background. Needless to say, higher contrast images work better with this tool. Even so, the Edge contrast and Frequency options can be adjusted in the Options bar to create more precise selections on less contrasty images. All of the Lasso tools will draw a straight line to close the path if it’s not completed. They also display a small circle next to the cursor when the path is closed.

To select based on color, the magic wand tool will do the trick. This tools works best on images where the foreground (or subject) color and the background are very different. Clicking on the color and then increasing/ decreasing the tolerance to add/subtract additional colors. To select the color throughout the image, uncheck the Contiguous button in the Options bar. The Magic wand can also be used to remove a color from a selection by using the “Subtract From” icon and clicking on the color.

For more sophisticated selecting based on color choose Select > Color Range. In the Color Range dialog box, a single color can be selected or, multiple colors can be selected by using the Eyedropper with the plus. A preview of the selection can be viewed in the mask area below. Additional options are available for selecting specific colors, highlights, shadows or midtones, and out of gamut colors (non printable based on your CMYK separation setup).

You can always add to, subtract from, and intersect a selection using the three icons on the Options bar. Use the following shortcuts to access these options without using the icons: Shift adds to a selection, option (Mac)/Alt (Win) subtracts from a selection and shift + option (Mac)/shift + Alt (Win) selects the intersection or “overlap” between an existing selection and a new one. Selections can be modified by choosing Select > Modify and choosing Border, Smooth, Expand, or Contract. They can also be manipulated by choosing Select > Grow, or Similar.