This process produces Bas relief using a darkroom-like technique. It effectively creates a monochrome inter-negative, binds it up "out-of-register" with the original, and then camera-copies it to brighten and make it permanent.

• Open a file;
• Drag the background to make a background copy layer (layers palette);
• Select the copy;
• De-saturate, then invert (this creates a monochrome negative);
• The interneg may now be posterized using 2 to 6 tones for different effects;
• Filter > other > offset (try 2 pixels in each box, as either plus or minus figures depending on the direction of shift required);
• Check the relevant box to ensure that the edge pixels are repeated;
• Select the background layer and create two adjustment layers;
• Layer > new adjustment layer;
• Select brightness & contrast, name it "more brightness" and set it at 50% normal;
• Accepting will give the usual brightness & contrast window;
• Set the brightness to 100%, and accept;
• Repeat naming the second new adjustment layer "more contrast";
• Set the first to 50% normal, then to between 60% and 80% in the brightness & contrast window;
• Select the background copy layer and drag it (if necessary) to be immediately above the background layer itself - this is important!
• Set the blending to 35% normal for the background copy layer;
• Select the "more brightness" adjustment layer and move the slider to brighten the image;
• Select the "more contrast" adjustment layer and move the slider to adjust;
• Flatten if required, alternatively select the background copy and change the blending to (say), 60% multiply;
• Repeat adjustments of the two adjustment layers as necessary. Try other values and blending modes for different effects; and
• Finally, flatten all the layers.