12 Step 12
Go to Channels Palette and create a new channel. Go to Filter > Render > Clouds. Now go to Filter > Render > Difference Clouds. We’ll apply this filter twice more, so Press Command + F twice. Now go to Image > Adjustments > Invert. Go to Image > Adjustments > Levels (Command + L) and set the Input Levels to 200, 1, 255. The white area in this image is going to be the eroded parts of the paint. Command-Click the channel to load the selection.
