Lastolite's Chromakey Collapsible Backgrounds are available in three sizes, 1.5x1.8m, 1.8x2.15m and 1.8x2.75m. Choose from Blue, Green or the new reversible Blue / Green variety. Chromakey is a process of substituting one background or colour for another in video. The most common examples of this are the weather maps shown on broadcast television. Once a difficult process requiring expensive equipment, it now can be done with any intermediate video editing program. Typically the subject is shot in front of a high key blue or green background which is then knocked out and replaced with another image or video superimposing the subject on the new background. Chromakey has been used in film and cinema productions as a tool to mix two or more images together in all aspects of the art. It is also increasingly used in photography to cut and paste a subject onto a background.