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There are many different effects that can be achieved using this combination of filters applied to two separate layers. This one gives an etched effect.
ORIGINAL IMAGE
1. To apply the filters to two separate layers, duplicate the Background layer twice by dragging it down to the Create a new layer icon at the bottom of the Layers palette.
2. With each layer, go to Filter > Convert for Smart Filters so you can adjust the settings later if you want to.
3. Select the Sponge layer and go to Filter > Artistic > Sponge. For this image, the settings to the left were applied.
SPONGE SETTINGS
4. Apply the Subtract blending mode to the Sponge layer.
5. Select the Underpainting Layer and go to Filter > Artistic > Underpainting. The settings middle left were used here.