Adobe Photoshop CS3 - Manual (Page 375)

PHOTOSHOP CS3
User Guide
368
Draw using the magnetic pen options
The Magnetic Pen is an option of the Freeform Pen tool that lets you draw a path that snaps to the edges of defined
areas in your image. You can define the range and sensitivity of the snapping behavior, as well as the complexity of
the resulting path. The Magnetic Pen and Magnetic Lasso tools share many of the same options.
1 To convert the Freeform Pen tool to the Magnetic Pen tool , select Magnetic in the options bar, or click the
inverted arrow next to the shape buttons in the options bar, select Magnetic, and set the following:
• For Width, enter a pixel value between 1 and 256. The Magnetic Pen detects edges only within the specified
distance from the pointer.
• For Contrast, enter a percentage value between 1 and 100 to specify the contrast required between pixels for that
area to be considered an edge. Use a higher value for low-contrast images.
• For Frequency, enter a value between 0 and 100 to specify the rate at which the Pen sets anchor points. A higher
value anchors the path in place more quickly.
• If you are working with a stylus tablet, select or deselect Pen Pressure. When this option is selected, an increase in
pen pressure causes the width to decrease.
2 Click in the image to set the first fastening point.
3 To draw a freehand segment, move the pointer or drag along the edge you want to trace.
The most recent segment of the border remains active. As you move the pointer, the active segment snaps to the
strongest edge in the image, connecting the pointer to the last fastening point. Periodically, the Magnetic Pen adds
fastening points to the border to anchor previous sections.
Click to add fastening points, and continue tracing.
4 If the border doesn’t snap to the desired edge, click once to add a fastening point manually and to keep the border
from moving. Continue to trace the edge and add fastening points as needed. If you make a mistake, press Delete to
remove the last fastening point.
5 To dynamically modify the properties of the Magnetic Pen, do one of the following:
• Alt-drag (Windows) or Option-drag (Mac OS) to draw a freehand path.
• Alt-click (Windows) or Option-click (Mac OS) to draw straight segments.
• Press the open square bracket key ([) to decrease the Magnetic Pen width by 1 pixel; press the close square bracket
key (]) to increase the pen width by 1 pixel.
6 Complete the path:
• Press Enter (Windows) or Return (Mac OS) to end an open path.
• Double-click to close the path with a magnetic segment.
• Hold down Alt (Windows) or Option (Mac OS), and double-click to close the path with a straight segment.