The Eraser Tool
A D V E R T I S E M E N T
The eraser tool shortcut
is E. The standard eraser tool has four painting modes to choose from:
paintbrush, airbrush, pencil, and block. These modes work just like their
painting tool counterparts, except for the block tool, which as you can probably
guess, is a simple square block. The difference is, instead of painting the
foreground color onto your document, the eraser tool paints in transparency...
Unless your layer is a background, in which case, the eraser tool paints with
the current background color.
The eraser tool options
are basically the same as the painting tools, with the addition of one new
option: Erase to history. When you erase to history, it works just like the
history brush. Instead of painting in transparency or the background color, you
are painting from the active history state in the history palette. You can
temporarily switch to Erase to History by holding the
Alt/Option key down while the
erase tool is active.
The Magic Eraser works just like the magic wand, but instead of making a
selection, it immediately converts the pixels to transparent. It's also very
similar to using the paint bucket in clear mode. The areas to be erased are
controlled by adjusting the tolerance and contiguous options. Clicking once
erases all the the pixels that fall within the tolerance range. If the magic
eraser is used on a background layer, the background is automatically promoted
to a layer.
This tool is best for when
you have a background that is fairly solid in color. It just takes one click
with the magic eraser and your background is gone. In general, though, you'll
need to experiment with the tolerance settings until you get better at being
able to eyeball the correct tolerance level.
The Background Eraser
The background eraser also erases to transparency, but instead of using only the
tolerance range, it continuously samples the background colors in your document
as you erase. It's useful for backgrounds that have a range of colors in the
background, but where the background colors are still distinct from the
foreground object you want to isolate. It works best with a fairly large brush.
To use it you would
position the crosshair over the color you want to be erased, and use a series of
single clicks to eat away at the background, or slowly drag along the edges of
the object you're trying to isolate.
The most important thing
to remember with this tool is to be very careful to keep the crosshairs away
from the object you want to keep. When using this tool, you may notice some bits
of the foreground object becoming slightly transparent along the edges. You
needn't be terribly concerned with this, because you can always paint those bits
back in using the Erase to History option or the History Brush.
The background eraser is a
great tool for quickly isolating an object, but it does have a tendency to leave
stray translucent pixels in the background. You'll almost always want to drop a
solid white background layer behind the object and do some cleanup after using
Now that you've been
introduced to these tools, it's time to start using them. Over the next several
pages, you will work through 10 exercises utilizing each of the painting tools
combined with many other features we've learned so far. Feel free to save your
work and post your results to the
interactive classroom. Before you begin, you'll need to download and unzip
which contains all the files you will need for these exercises. (Mac users can
use Aladdin's free
Stuffit Expander to extract the zip file.)