This way, footage shot in a small studio, or a closet draped with green-screen, can appear to take place in a sunlit valley or busy streetscape-and, if done correctly, can look very convincing. You can then drop the isolated subject onto a new background of your choice. Using editing software you then digitally remove, or key out, that color based on its chroma range-a process known as chroma keying. Using a green screen involves shooting your subject against a solid color backdrop, usually bright green. In other words, a green screen lets you superimpose one photo or video stream over another, making it look like a single stream. Green screen-sometimes referred to as blue screen, or as it’s technically called, chroma key-is a digital post-production technique for compositing, or layering, different video streams based on color hues. What is a green screen and how does it work? Today’s digital tools make green screen video accessible to DIY filmmakers. But you don’t need a Hollywood budget to create them yourself. These were the rudimentary beginnings of the green screen technique film studios still use to combine different shots and create all kinds of visual effects.

By blacking out certain parts of the frame, then re-exposing the film, he could combine different shots-each with his head photographed in a different place-into a single frame. Méliès was a pioneer of filmic special effects. Then, to the delight of his small bodiless audience, he took out a banjo and began to play. Another head then appeared on his shoulders he removed it also, placing it next to the first, and then did it again, leaving a headless Méliès standing amid three of his heads. Standing between two tables, Méliès plucked his head from his body and placed it on a table, where it continued talking. In his 1898 silent film, The Four Troublesome Heads, Georges Méliès played a visual trick that marveled his audience.

How to do green screen effect on imovie