Understanding visual effects techniques and their applications in audio-visual media products

Green Screen

1. Green screen is the technique of photographing or filming an object and/or an actor in front of a green monochrome background and replacing the background with a different image.

2. The first instances of image compositing for film started back in 1898 in a film called "Four heads are better than one". In this movie, the actor's head was duplicated doing different things in several different locations all at the same time and this was achieved by doing multiple exposures. Following from this the glass shot was developed. This was where glass panels were painted on to produce landscapes and other things to give the illusion of depth etc. These things led to the development of the Blue Screen. Like Green Screen, the Blue Screen was essentially the same thing where the object or actor would be filmed in front of a blue backdrop to make it easy to separate them from the background and replace it with something else. Later, after the use of the Blue Screen, film makers decided Green was a better colour. This was because it required less light to get good lighting from it. Chroma keying is what is used now to remove the green from behind the actor or object to insert a new background.

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Mattes and Matte Painting

1. A matte painting is a painted depiction of a landscape, set, or distant location that allows film makers to create an environment that is non-existent in real life or would be too expensive or impossible to build/visit.

2. In 1905, Norman Dawn used black tape to mask out things he didn't want to appear in his picture and then took the picture again using a glass panel with a painting in front of the camera to enhance his pictures by placing whatever was in the painting in his picture, Chris Evans was the first person ever to create a digital matte painting that would be used in a film. In 1985 Evans blended a scanned image with digital painting to create an extremely realistic scene that was placed in the film Young Sherlock Holmes. Now with everything becoming digital, Photoshop and 3D software is becoming used more and more to create matte paintings and backgrounds etc for films and photographs.