Adobe 13101332 - Photoshop - Mac User Manual page 160

Adobe Photoshop Help
Using Help | Contents
To use the magnetic lasso tool (Photoshop):
1 Select the magnetic lasso tool
lasso, polygonal lasso, and magnetic lasso tools" on page
2 Click in the image to set the first fastening point. Fastening points anchor the selection
border in place.
3 To draw a freehand segment, move the pointer along the edge you want to trace.
(You can also drag with the mouse button depressed.)
The most recent segment of the selection border remains active. As you move the pointer,
the active segment snaps to the strongest edge in the image, based on the detection
Width set in the options bar. Periodically, the magnetic lasso tool adds fastening points to
the selection border to anchor previous segments.
4 If the border doesn't snap to the desired edge, click once to add a fastening point
manually. Continue to trace the edge, and add fastening points as needed.
5 To switch temporarily to the other lasso tools, do one of the following:
To activate the lasso tool, hold down Alt (Windows) or Option (Mac OS), and drag with
•
the mouse button depressed.
To activate the polygonal lasso tool, hold down Alt (Windows) or Option (Mac OS),
•
and click.
6 To erase recently drawn segments and fastening points, press the Delete key until
you've erased the fastening points for the desired segment.
7 Close the selection border:
To close the border with a freehand magnetic segment, double-click, or press Enter or
•
Return.
To close the border with a straight segment, hold down Alt (Windows) or Option
•
(Mac OS), and double-click.
To close the border, drag back over the starting point and click.
•
Setting options for the lasso, polygonal lasso, and magnetic lasso
tools
The lasso tool options let you customize how the different lasso tools detect and select
edges.
To set options for the lasso tools:
1 If needed, select the tool.
2 In the options bar, specify whether to add a new selection
selection , subtract from a selection
selections .
3 Specify feather and anti-aliasing options. (See
page 166.)
4 For the magnetic lasso tool (Photoshop), set any of these options:
To specify a detection width, enter a pixel value for Width. The magnetic lasso detects
•
edges only within the specified distance from the pointer.
Using Help | Contents
| Index
, and select options. (See
, or select an area intersected by other
| Index
"Setting options for the
160.)
, add to an existing
"Softening the edges of a selection" on
Selecting
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