Visual Effects
Visual effects are used to enhance or create a visual image. They are usually added post-production with the use of animation, modelling, graphic design and similar software.
History of Visual Effects
Films have always tried to create illusions even from the earliest times. One of the first examples of a stage effect was Pepper's ghost, where lighting and plate glass were used to make an object (ghost) appear and disappear or morph into another character. This was first demonstrated in the 1860's and adapted for film by Eugen Schüfftan (1893–1977) to put actors into backgrounds using mirrors. It was used extensively until the mid 20th century but has now been replaced by travelling matte and bluescreen effects.
Film effects were divided into optical effects, mechanical effects and atmospheric effects and together were called special effects. With the advent of digital film-making a new distinction arose between special effects, done during production and visual effects, usually done post production.
Optical effects are techniques that can be created photographically, for example multiple exposures or 'mattes' (where multiple images are built up, to create a background) or in post production to place actors against a background.
Mechanical effects usually take the form of models, scenery and pyrotechnics used during filming. They can involve illusions like cars driving themselves or prosthetic make-up.
Atmospheric effects are those involving the creation of wind, rain, snow fog or other similar effects.
The first film special effect has been recorded as the beheading of Mary Queen of Scots (1895) created by Alfred Clark. This was simply done by stopping the camera and then replacing the actor with a model just before the axe came down.
The French magician Georges Méliès was referred to as a "Cinemagician" because of the huge number of effects the he developed using multiple images, matte painting, time lapse photography and the combination of animation with live action in films for example Le Voyage dans la lune, 1902. During the early 20th century special effects developed further. There were improvements in matte painting, Norman Dawn painted the film black rather than using cardboard to block exposure of the film. He then projected the film onto an easel so that the background could be painted in perspective much more easily. The development of mattes to layer There were huge steps forward in prosthetic make up, that were used especially in horror movies.
Another simple techniques was also the use of models for ships, tanks and aeroplanes. These could used and combined in various ways to produce new effects.
A number of other optical effects were developed over the years these included fades, dissolves, wipes, blow ups, skip frames, double exposures, and zooms/pans .
With the advent of colour photography bluescreen and compositing can be used to layer two images together more easily. The development of the bluescreen was credited to Larry Butler for use on the Thieves of Bagdad. The actor performs in front of a blue screen and the background is added. An optical printer with two projectors is needed to combine these images frame by frame. Now because digital cameras retain more detail in the green channel the screens are often now green not blue.
Methods of producing more modern visual effects included cel animation, scale modelling, claymation, digital compositing, animatronics, morphing, and modern computer-generated or computer graphics imagery (CGI).
