Lasso & Wand
A D V E R T I S E M E N T
The regular lasso tool
allows you to make freehand selections. Just click and drag to draw the
selection. Whenever you let up on the mouse button, your selection will
automatically close, forming a straight line between the start and end points.
The shortcuts for adding to and subtracting from the selection are the same as
the marquee tools. Here's some additional lasso tool shortcuts:
- If you want to
draw straight lines with the lasso tool, you can hold down the
key and make a series of single clicks instead of dragging.
- You can toggle
between freehand and straight line mode by pressing the
key while you are drawing the selection. This is a bit tricky, you need to
make sure you press or release the key wile the mouse button is down or you
will close the selection.
- You can hold down on
the delete key to erase recently drawn line segments.
You also have feathering
and anti-aliasing options with the lasso tool.
The Polygonal Lasso tool
is used to draw straight line selections. You can make the polygonal lasso tool
work just like the regular lasso tool by holding down the
key to draw freehand selection. One difference with the Polygonal lasso tool is
that you can use the Shift key to constrain the selection lines to 45°
increments. If you are drawing a straight line selection you can press the
delete key at any time to remove the last segment. To remove multiple
segments, press delete repeatedly.
If you used the polygonal
lasso tool to make a freehand selection you can hold down the delete key
to slowly erase the line. This also requires a bit of coordination, because you
will have the Alt/Option
key already held down to draw freehand. What you need to do is let up on the
key and hold down delete. Then when you have erased as much as you'd
like, you can go back to pressing down the Alt/Option
key to continue your selection in freehand mode.
Magnetic Lasso tool works similarly to the other lasso tools, but it has special
powers that can detect areas of contrast and it will snap to the edges of the
object you're trying to select. Because of these special powers, the magnetic
lasso has more options than the other lasso tools. These options are explained
magnetic lasso tutorial, which is part of the assignment for this lesson.
You can temporarily switch
to the regular lasso tool behavior while using the magnetic lasso by holding
down the Alt/Option
key and dragging. Or you can temporarily switch to polygonal lasso tool
behavior by holding down the Alt/Option
key and clicking. The Delete key allows you to delete points.
Here's some additional lasso tool shortcuts that aren't mentioned in my
- You can adjust the
lasso width as you draw using the arrow keys or the [ and ]
- You can adjust the
frequency as you draw using the ; (semicolon) and '
- You can adjust the
edge contrast as you draw using the , (comma) and . (period)
Closing selections with
the polygonal lasson and the magnetic lasso is a little bit different than the
freehand lasso tool. With these tools there's two ways to close the selection:
- If you move the
cursor within a few pixels of the starting point, you'll see a tiny circle
appear next to the cursor and it means that when you click once the
selection will close.
- If you're not near
the starting point and you want to close the selection you must double
- If you're using
the polygonal or magnetic lasso tool with the
Alt/Option key to make
freehand selections, you must let up on the Alt/Option
key first, and then you can double click to close the selection.
but not least, is the Magic Wand tool. The magic wand makes selections based on
color similarity. The shortcut for the magic wand key is W.
click on the magic wand tool to bring the options palette to the front.
setting controls the range of color that will be selected and has a range from 0
to 255. To select a small range of colors enter a low number, for a wider range
of color, select a high number.
The Use all Layers
option allows you to select based on the data from all visible layers (we'll be
learning more about layers in the next lesson).
for Version 5.0
contiguous option is only available in version 5.5 and higher.
When contiguous is
checked, the selection only includes adjacent pixels of the same color
range. If you wanted to select islands of color all at once, you would deselect
the contiguous option.
As with the other
selection tools, you can use Shift to add to the selection, and
to subtract from the selection.