Adobe Photoshop CS2 On Demand [Electronic resources] نسخه متنی

Using the Magnetic Lasso Tool

The Magnetic Lasso creates a selection by following along the edge of a visible object. For example, it will follow around the edge of a building that contrasts against a bright blue sky. In reality there are no edges in a photographic document, so the tool follows along the shifts of brightness created when one image interacts with another. Select the Magnetic Lasso tool on the toolbox from the available Lasso options. Click on the visible edge of an image (like the edge between building and the sky), and then move (don't' drag) abound the object. The Magnetic Lasso will follow the visible edge of the object; occasionally adding anchor points to the line as you move. Double-clicking the mouse instructs the Magnetic Lasso tool to close the selection shape.

Use the Magnetic Lasso Tool

Select the

Magnetic Lasso tool on the toolbox.

Click the

Preset Tool list arrow, and then select from the available tool presets.

Use the selection options on the Options bar to create a new selection, or add, subtract or intersect an existing selection.

Enter a numerical value (0 to 250) in the Feather box to create a feathered selection edge.

Select the

Anti-alias check box to create a softer selection (useful with intensely rounded or curved selections.

Enter a Width value (0 to 256) to instruct the Magnetic Lasso tool how many pixels to consider for the edge.

Enter an Edge Contrast value (0 to 100) to instruct the Magnetic Lasso how much of a shift in the brightness values to use in determining the edge.

Enter a Frequency value (0 to 100) to instruct the Magnetic Lasso where points are added to the selection line.

Click once to create an anchor point, and then move the pointer along the edge you want to trace.

If the border doesn't snap to the desired edge, click once to add a anchor point manually. Continue to trace the edge, and add anchor points as needed.

Double-click or click the starting point to complete the selection.

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