| Green Material. Place a piece of green material by clicking on the green Material button and then clicking in either the Material A Region or the Material B Region. To see how the percentage of incident light reflected by green material varies by color, click the Open Material A Graph or Open Material B Graph buttons. To see the spectrum of light from a particular source reflected by green material, use the Spectroscope tool. To model the reflection by a "perfectly" green material, use the Ideal Material tool.