Rear Film Size:1.52*30m Color:(RG2) Light Grey Film Thickness:100m Light Transmission:81% View Angle:120 Contrast: ... etc..which color? Answer: Usually, transparent, white, light grey are suitable for dark environment.Dark grey, natural black are suitable for daytime usage, so ... , better the film choose the high contrast type .like the grey color and choose the projector with the higher lumen to ...