Understanding Diffusing light

Sometimes you may find that a light you’re using to illuminate a subject is too intense. This is especially common with key lights. If all you’re getting is a glaring white spot on your subject’s face, you can diffuse the light by putting something between it and your subject:
_ Cheesecloth: Available at art and cooking supply stores (and some grocery stores), cheesecloth has a coarse mesh and is useful both for diffusing light and straining beans or cottage cheese in the kitchen.
_ Translucent plastic: Sheets of translucent plastic are also available at arts and craft stores. Professional videographers call these gels. Colored gels are often placed in front of lights that illuminate a backdrop for special lighting effects. If you do this, make sure you place a barrier between your key light and the backdrop so the colored light from the gel isn’t washed out by the white key light. A barrier may simply be a piece of cardboard that is held up by a stand or helper. If you diffuse your light, you may have to move your lights closer to the subject.
Experiment for the best results.
Lights (especially halogen lights) tend to get very hot. To avoid fire hazards, you must use extreme care when placing gels or cheesecloth in front of lights. Never attach diffusers directly to lights. Position your diffusers some distance away from the lights so that they don’t melt or catch on fire, and check the condition of your lights and diffusers regularly. Read and heed all safety warnings on your lights before using them.