Eraser

Eraser works with the Undo command. When selected you can "paint" a previous undo step.
That is, if you made a mistake, you can press the Undo button, or if you want to just correct a part of it, you can use the Eraser to remove only the area you wish.

Remember:

• The Eraser only goes one step back, so as soon as you make a mistake you have to stop painting and use the Eraser.
• You have to do at least one editing step to the image in order to use the Eraser.
• To return the image to it's original state, use Original Brush.
• With standard brushes, Eraser doesn't change the brush library - it erases with the last brush you selected. When you paint with Image Hose or Artistic brushes it actually uses the Library from Rubber Stamp - which is a good mixture of hard and soft brushes to select from.(You can create your own custom brush as well, and add it to the library.)

Fun with Hold Undo.

There is another command worth mentioning: The Hold Undo button.

Until it is pressed, the Image in the Undo buffer is locked and preserved. That means you can save an important Undo step for a while. When you Uncheck the Hold Undo button and use the Undo or Eraser command, it will use the saved buffer.

Note: When the Hold Undo is checked you can't use Undo, but (and this is important) you can use Eraser. Eraser will paint back the saved state of the image when you press Hold Undo.

You may not see it at this time, but there are many ways you can benefit from it.

When you are working with images on disk you have the Original brush (see Photo Retouch), so you can always go back to the original. With Hold Undo you can also preserve the step that you made any adjustment at, and you can switch between Eraser and Original brush to put changes back & forth.

Example:

We load an image from the disk so the Original is automatically defined.	Now let's make some adjustments to the whole image, here for example we used Sepia.	Now It is the time to push Hold Undo Button so the Sepia image will be preserved in the Undo buffer even if we do something else.	Now with Original brush "reveal" the original image. If you made a mistake, don't worry - you can paint back the "locked" Sepia state with the Eraser.

When you finish, Uncheck the Hold Undo so normal Undo operations can work.

This simple command makes retouching much easier. You can have 2 "saved" appearances of the image. One is the Original (and you can set any step as Original with menu Image->Set as Original) and the other one is in the Hold Undo buffer.

Remember, if you don't press Hold Undo, you can still use Eraser, however, it then will work only on one step back, so you have to stop painting and fix the problem as soon as it appears.

When you have Undo on Hold, resizing of the image isn't a good idea, unless that's the effect you want to achieve, since the two images will be of different physical size.