Light

Parts of your sheet that ripples are usually clearer and other parts are in the shade. This is quite logical! We are going to use the airbrush on a new layer to simulate this shadow with the greatest possible accuracy:

1. Create a new layer (call it Layer 2) and set the mode to Multiply.
   
   
2. Ctrl-click on Layer 1 in the Layers palette.
   
   
The purpose of this step is to create a selection that is the same shape as your sheet. In this way, you will avoid any overflowing when you use the airbrush. Furthermore, by working on a separate layer, you will avoid damaging the original image if you make a mistake.


3. Select a foreground colour for the shading (we have used the following RGB values here: 153, 153, 0).
   
   
4. Select the Airbrush Tool with a size of 35 pixels. It is better to go for a rounded shape, as this is more realistic for drawing a shadow.
   
   
5. Set the pressure of your Airbrush to 10%.
   
   
Your shadow will be very light and you can make it stronger little by little.

When you are satisfied with the result, deselect all and then select Layer > Merge Down. Your sheet and its shadows have now been grouped together in a single layer.



Figure 7: We've added a little depth, but it's not finished yet!