Green screen is a modern day technique that many industries use to make a movie, making it easier to place a character in an environment without physically putting them there. One of the first green screens used in the film industries was in the 1930’s by Linwood Dunn to create windshield wipers on a car shot. Green screen is a modern day of media as it can be used for photography, film, news shows as well as music videos and live action videos.
Below we can see the use of green being used for the rap battle music video produced ‘Ghostbusters Vs Mythbusters’ by Pete Shukoff, LLoyd Ahlquist and Maker Studios. This YouTube channel is a great example as they animate several different scenes for each shot and put several characters in a shot even when there will only be one during filming. Additionally we can see the difference that colour keying can make in films such as ‘The Hobbit’, ‘Alice in Wonderland’, ‘300: Rise of the Empire’, ‘Endersgame’, etc. With this effect it makes the film set an overall safer place as explosions and high platforms can be edited in rather than putting the actor(s) in that environment.
The green screen effect is also known as colour-keying, colour-separation overlay (CSO) and the reason as to why the screens tend to blue and green are because they contrast skin colour the most. With recording on a green actors and items have to avoid wearing green and/or blue as they will go transparent in the editing process. The process to do this effect can be done in either be done in Photoshop or After Effects, in the video below we can see a tutorial about how to do CSO in After Effects. The tools mainly used in this process are ‘Remove Grain’, ‘Key Light’, ‘Screen Balance’ and ‘Screen Gain’.
As I have never done this technique before when it comes to editing, it will be a challenge as first, however once I begin to practice with different video clips then I will be able to get the hang of it when it comes to both the 20 second trailer and longer trailer.