VFX - Green Screen

A green screen can be used in film and television techniques such as chromakey, and they are used as a background so the moving objects and people in front to be filmed with a completely separate background which can be added in later as a form of an image or video. Using a green screen will allow the moving people and objects to appear to be anywhere, from Japan to a Desert.


Key parts of the history of green screens:

• In filmmaking, a time-consuming process called "travelling matte" was used before digital compositing was invented.
• The blue/green screen method was developed in the 1930s at RKO Radio Pictures.
• At RKO, Linwood Dunn used an early version of the travelling matte to create "wipes" - where there were transitions like a windshield wiper in films such as Flying Down to Rio (1993).
• A scene featuring a genie escaping from a bottle was the first use of the proper green screen process to create a travelling matte, for The Thief of Bagdad (1940).
• The development of the green screen is credited to Larry Butler, who won an Academy Award for special effects in The Thief of Bagdad.
• One drawback to the traditional travelling matte is that the cameras shooting the images to be composted can't be easily synchronized. For decades, such matte shots had to be done "locked-down", so that neither the matted subject nor the background could shift their camera perspective at all.
• Later, computer-timed, motion-control cameras alleviated this problem, as both the foreground and background could be filmed with the same camera moves.

One example of a use of the green screen is in Ugly Betty, when she is trying to be interviewed but she runs into the bus shelter (0:38). It was used in place of filming in the actual streets of New York for a variety of reasons: it would make it easier to control the ambient noise (the streets of New York would be very loud with the traffic noises and the people rushing around. It was used in an interesting and convincing way because the new background that has been created with the green screen is just as realistic as the actual streets of New York - in fact it looks so convincing that you wouldn't be able to tell unless you were told. Therefore, it's very convincing because the technology used today is so great.