Using a Green-screen can be an important part of a work flow. Knowing which type of material to use can reduce the time spent on post production. One issue that most users face is of colour fringing. This occurs from light rays being reflected of a hard surface such as paper. Looking at the image of the cloth ( left ) we can see a close up of the structure of the material. The light rays do not have a hard surface to bounce off and therefore the result using this material will be less likely to cause spill around the edges of your subject matter. This type of fringing which occurs from spill can be reduced in post using various methods. Using cloth has some worthwhile benefits in this regard, however there are some downsides. The cloth can be difficult to keep flat and seamless. The Green-screen cloth I use is held together in a flexible frame that stretches from end to end and is portable. It is large enough to accommodate one head and shoulders, where as paper roll can accommodate at least 5-6 people from tip to toe. Having both paper and cloth as part of your equipment is essential for anyone doing composites with green screen.
Reflection and the varying degrees of the angle of incidence
This is the difference between a rough and a smooth surface such as the cloth and paper. When the light strikes the cloth the rays are reflected at different angles and may also pass through the gaps in the cloth. Light that strikes the paper will be reflected back at a more consistent angle and intensity toward the talent positioned in front of the Green-screen.The result in most cases will be a green fringe around the talent. I say in most cases; as the cause can be reduced if the talent is brought further away from the point of the reflected light.
The Sony F3 was used for the Green Screen composite above. The studio was lit with Two cyclorama lights on the green cloth. The couple were lit with two Kenos and three Dedo for effect.