Animation is the process of displaying still images in a rapid sequence to create the illusion of movement. These images can be hand drawn, computer generated, or pictures of 3D objects. Though most people associate animation with cartoons, it also has applications in industrial and scientific research. Regardless of the type, the viewer's body plays a main role in why people see continuous movement instead of a series of quickly changing images.
Types
There are three main types of animation: traditional, stop motion, and computer generated. Each can be used to make both 2D or 3D images. There are also other less common forms, many of which focus on using an unusual medium like sand or glass to create the images, as well as combination of live action and drawings or computer created images.
Traditional
Traditional animation involves drawing every frame of a film by hand. After all the drawings are completed and colored, they can be photographed or scanned into a computer and then combined with sound on film. The process is extremely time-consuming, since it requires the creation of around 24 drawings per second of film. It's also labor-intensive, which is why most traditionally animated films are produced by large companies.
Stop Motion
In this process, animators manipulate and photograph objects one motion and frame at a time. The objects can be almost anything, ranging from clay figures to paper cut outs to household objects. Some stop motion films use actual people, who hold specific poses for individual frames. After photographing the objects, the photos are then transferred to film and combined with sound, as with the traditional method.
Computer Generated
Animators can also use computer software to create films and models, which is generally faster than the traditional method. The characters and objects they make can be either two-dimensional or three-dimensional, but the process for creating each type is a little different. For 2D computer generated animation, the animator creates a series of images with each one very slightly different from the last, very similarly to the traditional method. To create 3D images, he or she has to make a model of the character or object. This can be done by creating animation variables, which are points on a computer model that can be moved to create a different posture or look, or by using motion capture, in which a live actor acts the part of the character and his or her motions are recorded and applied to the computer-created model.
Uses
Though most people think of animation as being used primarily for entertainment in movies, TV shows, and video games, it has many other uses. It's commonly used in educational videos and advertisements both on TV and on the Internet, and it can also be used in the process of research and development to create simulations of how a machine or process would work. This can help designers troubleshoot problems without having to actually create the physical object. Scientists use animation as well to create visualizations of abstract concepts or objects that are too small or large to be seen easily, which is helpful both for research and for analysis.
Role of the Viewer
Animated films and models aren't actually moving, but people see the illusion of movement because of a phenomenon called persistence of vision. In this phenomenon, the brain and eyes cooperate to store images for fractions of a second, and the brain smooths out any minor jumps or blips automatically. Since animated frames are shot at very fast rates, people generally see the movement without stoppages.
