 As DMX control value increases, it progresses the scroll further and the holes become smaller and less numerous - so the percentage of coloured material in the optical path increases relative to the white light pass-through, and the result is progressively higher density colour transmission.Ultimately, at full DMX, a solid, unperforated sheet of gel is positioned in the optical path - for full saturation.colour scrollers come in many different sizes and are mountable on nearly every type of conventional lighting instrument.