P1 Research and Understanding Green Screen

Green Screen is used in a special effects technique called Chroma Key Composting or Chroma Keying. Chroma Keying is a technique for compositing/Layering two images or videos together.
In 1898 George Meles made a film called four heads are better than one in the film he used mattes to composite several versions of is head onto tables, he did this by blacking out the part of the frame where he wanted his heads to be with pieces of glass that he painted black he did this to make sure those parts of the film wouldn't get expose. Meles would then rewind the film and matte everything else in the frame and expose what he had matted before. Edwin S. Porter also used this technique in 1903 for his film The Great Train Robbery, Porter composted moving scenery and trains into his scenes. The trouble with this process was that know one could pass the matted section and the camera had to be perfectly still. In 1918 Frank Williams patented the Traveling Matte this was a process like green screen but the background the actors where performing against was completely black it was used in a film called Sunrise. In 1925 the Dunning Process was made by C. Dodge Dunning, the Dunning Process would have actors in front of a blue lighted screen and have the actors/foreground lighted in yellow the Dunning Process was first used in 1933 in King Kong but the Dunning Process only worked with black & white films. In 1940 Larry Butler created a technique that could be used for color film, Butler shot the actors in front of a blue background. He used the technicolor 3 strip process and took the negative and create a silhouette matte he then used an optical printer to combine the foreground and background plate together. Petro Vlahos created the sodium vapor process. The process involved actors standing in front of a white screen lit by sodium vapor lights that made it yellow, this process was used a lot by Walt Disney e,g The Parent Trap and Mary Poppins.

Special and Visual Effects in The Walking Dead

The Walking Dead is one of my favorite TV shows at the moment and watching the video I was surprised how much they add in post production. The green screen effect I have chosen is the ones above because when I watched the episode I never would of thought that they would need green screen for this and adding a helicopter blade in the post edit. The purpose of the shot is to convince the audience that Rick has woken up to find the world decayed and stopped working, The Walking Dead are good at making there scenery and zombies looking believable but for this scene I don't think they actually need the green screen because all they add into the scene is a few army cars, helicopter propeller, tents and props which they could of easily done with out the green screen, but with the green it was probably a lot easier and quicker to shoot than actually having the props already in shot.