Selecting a sample dish depends on the color uniformity and granularity of the product you wish to measure. For smooth, uniform samples such as opaque pastes, spices, or finely ground samples, use the optional 4 inch (100 mm) petri dish and disable the turntable motion. For medium color uniformity and granularity (such as peanuts or plastic pellets) use the 6 inch dish. For highly irregular sample surfaces or large, non-uniform color samples such as cookies, use the nested configuration of the 6 inch and 12 inch pan. The number of rotations can be increased for non- uniform color samples. Typically use 1 rotation for uniform color samples and 2 -3 rotations for non-uniform color samples.