You can also make bounce cards from aluminum foil taped over cardboard to bounce light back in on the oposite side the main light is coming from. THat lets yoo control the shadow side. You can use cardboard to block light too. THe smaller the light source the more defined shadows are. The larger the light source the softer the shadows. You can shut off all the lights and use a flashlight to paint with light. Play with it. Have fun. Experiment.