Film and television production companies are continually asked to render scenes ,that seem to be beyond the limits of their software and hardware. To complete ambitious 3D renderings with the required complexity, quality, and speed, almost all professional productions are rendered in multiple layers or passes and finished through compositing. Compositing is the art of combining multiple images into a unified final scene. Multi pass rendering and compositing allow for more efficient rendering, increased creative control, convincing integration with live-action footage, and rapid revisions of shots.