Kindofsmile Softbox Flash Bounce Diffuser Speedlight Yn560 Ii III Yn-565 Yn-468 Yn-467 Yn460 The diffuser is used to create exposures of even density over the entire surface of film. Use the diffuser by placing it flush against the front of the lens and exposing through it. The light that passes through the diffuser and on to the film will create an even density across the surface of the film.