Difficulty: Moderately Easy
Step1
To use the History Brush, you must first take a snapshot of an image. Make the changes you want to make and then select a “state” of the image from within your History Palette.
Step2
Next, click the New Snapshot button at the bottom of the History palette. The icon looks like a little camera. This will automatically create a new snapshot. If you want to be able to set options for the snapshot, choose “New Snapshot” from the History palette menu.
Step3
To give a snapshot a new name, double-click on it and enter the name.
Step4
Next, select the History Brush tool from the toolbox. It looks like a paintbrush with an “action arrow” going around it.
Step5
In the Opacity options bar that opens, you can choose the opacity and blending mode for the brush.
Step6
Next, go to the History palette and click on the square to the left of the state or snapshot that you want to use as the source for the History Brush tool.
Step7
Go back to the snapshot that you wish to alter and drag the History Brush tool over the areas to be changed.