Visual Effects: Activity 1

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Visual Effects Beginnings

Special effects artists make things happen in movies that might not normally occur in real life. When the real thing is too expensive, too dangerous or impossible to shoot, special effects artists are brought in. The term “special effects” first appeared in screen credits in the 1926 Fox film What Price Glory?, but special effects have been part of motion pictures from the beginning.

There are two major types of special effects. Visual effects include all types of image manipulation, whether they take place during principal photography or in post-production. Physical effects, also called practical effects, are performed live using “real world” elements. These include explosions, weather effects and stunts.

One of the phenomena that make motion pictures possible is “persistence of vision.” Persistence of vision describes the ability that the human eye has to briefly retain an impression of an image after it has disappeared. This allows the brain to read a rapid
series of images as an unbroken movement.

Georges Méliès, a French magician and filmmaker working in the late 19th and early 20th centuries, was among the first to exploit persistence of vision for magical effect. Méliès discovered that if he stopped the camera for a moment, moved or changed the object he was filming, and then started the camera again, he could make objects appear to turn into people or into different objects. In his 1899 film Cinderella, for example, Méliès turned a pumpkin into Cinderella’s elegant coach. This technique is known as stop-motion photography and is still used by animators and visual effects artists. In addition to stop-motion, Méliès employed such techniques as double exposure, fast and slow motion, and dissolves to create his “trick films.”

With The Great Train Robbery (1903), American Edwin S. Porter introduced visual effects that, rather than trick the audience, added to the film’s realism. Using a matte, a device that prevents a portion of the film from being exposed, he combined footage of a robbery inside a telegraph office with a separate shot of a moving train. When projected, the train appeared to steam past the window as the action took place inside.

Split-screen techniques using mattes enable actors to play more than one part in the same scene. After a portion of the lens is covered, the actor is filmed playing one character. Additional exposures, masking other portions of the film, are repeated as necessary.

In his 1921 film The Playhouse, Buster Keaton played multiple roles including, in one scene, an entire theater audience, a band leader, all the members of the band, and the dancers on stage. In another scene, he appears in nine different roles simultaneously. A special box with nine “gates” that could be opened one at a time as he performed each part was built for this sequence.

Stationary mattes (often called hard mattes), like those mentioned above, cover a fixed area, for example, the window of a train station. Traveling mattes are created by tracing the silhouette of a moving character or object and are different for each frame of the film. Mattes, background, and performance are then combined into one image.

Patented by Max Fleischer in 1917, the process known as rotoscoping, which uses a downward pointing camera mounted on a frame, was originally intended to help animators draw lifelike animation by tracing a projected film of an actor frame by frame, as was done in Snow White and the Seven Dwarfs (1937). It is one of the ways visual effects artists create traveling mattes.

In the mid-1920s, Eugene Shuftan, a German cinematographer, developed a method of using mirrors to combine models and miniatures with full-scale sets. The Shuftan Process was used in a number of scenes in German director Fritz Lang’s 1926 film Metropolis, which also employed animation, matte painting, rear projection and mechanical effects to create its vision of a futuristic city.

Matte paintings, either on glass or on other surfaces, re-create historical scenes or depict imaginary landscapes, fill empty skies with clouds, or substitute for elaborate interiors. When viewed through the camera lens, painted artwork blends with constructed sets and live action to produce an illusion of reality.

Models and miniatures are copies of people, animals, buildings, settings and objects. They can be smaller than real life, life-size or larger than the objects they represent, depending on the way they will be used. Miniatures or models are used to represent things that do not really exist, or that are too expensive or difficult to film in reality, such as explosions, floods or fires. The dinosaurs in When Dinosaurs Ruled the Earth (1971) and the Snow Walkers in The Empire Strikes Back (1980) were animated models. Miniatures portrayed the destroyed Los Angeles skyline in the 1974 film Earthquake.

Forced perspective is the optical illusion that exaggerates how much larger things closer to the viewer appear than things that are far away. In the 1942 film Casablanca, forced perspective was used to make the final scene, shot in a studio, look as if it had been filmed at an airfield. A smaller-than-life-sized cardboard model stood in for an airplane, its size making it seem far away. To increase the sense of distance, little people portrayed airport mechanics, and fog effects obscured the deception.

Slow-motion, fast-motion and time-lapse photography are some of the simplest visual effects. Scenes filmed at slow speed move faster than normal when projected at regular speed. This effect has been used in comedies since the silent era. It also makes it possible for car chases and other risky stunts to be performed safely at a slow speed. When scenes filmed at a fast speed are projected at normal speed, small animated models appear to move with deliberation like weighty, giant beasts. In time-lapse photography, the camera snaps a photo at set intervals. When the footage is projected, time is compressed, reducing the growth of a plant to a few seconds of screen time, for example.

With models and miniatures, stop-motion animation, miniature rear projection, and traveling mattes, among many other techniques, Willis O’Brien and other special effects artists created an imaginary lost world in the 1933 film King Kong. Techniques developed for this film are still employed by visual effects artists today, although now they may be produced in the computer.

Kong, the giant ape, was portrayed in most scenes by an 18-inch puppet covered in bear fur, with rubber tendons stretched between his joints. For closeups, the visual effects crew built a giant head, arm, hand, and foot of Kong. Three to four men inside the head operated the cables, levers, and compressed-air devices that controlled Kong’s features.

Rather than create elaborate sets or try to film on location, King Kong’s filmmakers used rear projection. In rear projection, the camera shoots actors performing in front of a translucent screen while a previously filmed scene is projected on the back of the screen. In one scene, for example, actress Fay Wray hides in a treetop while footage of Kong fighting a tyrannosaurus is projected in the background.

Dynamation, developed by stop-motion animator Ray Harryhausen for the low-budget 1953 film The Beast from 20,000 Fathoms, used rear projection in a different way. Live action footage of actors in real surroundings was rear-projected frame by frame and models were then animated in relation to the action behind them.

Have your students make a thaumatrope to demonstrate persistence of vision. On a cardboard disk or rectangle, have your students draw a simple image, such as a bird, on one side. On the other side, draw a corresponding image, for example, a cage (upside down in relation to the bird). Some other possibilities are a lightning bolt and sky, a fish and water, a cactus and desert, or a bare tree and leaves.

Instead of drawing the images, students may also use pictures cut from magazines or their own photos. They may also combine photos and drawings—for example, a photo of a friend on one side and a drawing of a hat on the other. Ask the students to punch two small holes a quarter-inch in on opposite edges of the disk, in line with the middle of the images. Then have them cut two pieces of string about eight inches long and attach one string to each of the holes. To make the disk spin, have them pull the threads tight and twirl them between the thumb and forefinger of each hand. As the disk spins, persistence of vision makes the images on the two sides appear to blend into one. Discuss with your students the relationship between persistence of vision and special effects.

Supplemental Activity

To show your students how matte paintings work, start with a large photograph or clipping from a magazine. Then, using a piece of glass or clear plastic, have them alter some of the features of the picture, either by cutting out additional images or by painting on the glass or plastic. For example, they might replace telephone wires with clouds or mountains, put a roof on a flat building, replace a car with a horse and buggy, or add water where there is a lawn. Suggest that they incorporate forced perspective into the scene, using scale to suggest distance. If you have access to a digital camera, have your students practice combining the matte with three-dimensional objects.

Visual Effects: Seeing is Believing

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Complete Visual Effects Activities Guide (PDF)

Activity 1: Visual Effects Beginnings

Activity 2: Physical Effects

Activity 3: Computer-Generated Effects

Activity 4: Visual Effects in Non-Effects Movies

Bonus Material Related to the 79th Annual Academy Awards Poster

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