You can also take the ambient attribute and link it to the image map node. Setting the ambience amount somewhere between .2 and .4 is good for softening the lighting and makes it possible to use a single light (thus speeding the render). The enclosed image is done this way. Yes that's DinaV wearing Koz'z Alice Hair and rendered with Firefly with mapped shadows but raytraced otherwise and DOF set up on her chest with F stop at 5.6. The wall is just a scaled up square with a 2D brick node attached to its diffusion and ambience. For Dina's body parts the diffusion is at 1 and ambience at .4. For the wall I went to diffusion .5 and ambience .2. That's the real advantage of procedural shaders. You can change the way each object in the scene is rendered. You can even hook an image map (or movie) to the ambience channel of a flat rectangle and use it as a virtual process screen!