A green background in front of which moving subjects are filmed and which allows a separately filmed background to be added to the final image. The green screen is an integral part of the special effects process known formally as chromakey. Chromakey allows television producers and movie makers to use advanced technology to superimpose their subjects onto an unlimited number of different virtual backgrounds.
How does it work?
A color range in the top layer is made transparent, revealing another image behind. The chroma keying technique is commonly used in video production and post-production. This technique is also referred to as color keying, colour-separation overlay (CSO; primarily by the BBC[2]), or by various terms for specific color-related variants such as green screen, and blue screen
Name films that use this effect?
1. Alice in wonderland
2. The hunger games
3. Iron man
4. Life of Pi
5. Harry potter
6. Superman
Think of a one minute scene that you could make using the green screen?
There could be a person running past the screen making it look like they're running through a location and then the location could change as they run past or out of the forest.
Or there could be a moving image of a cave exit and someone pretending to run out of it showing them from the back and when they get out of it, they could then change it to another location outside the cave with the person walking from the front view and then the location zooming out as they walk.
