The basic form of animation uses the simplest tools for drawing out the images. One can use pens, pencils and paper for this, but the more professional method uses paints and transparent sheets called "cels." Characters are outlined in black ink and then the artist fills in the color on the reverse side; the color is therefore visible on the front while not overlapping the outline. With all the drawings laid in order, the camera shoots one drawing at a time for a single frame; A full second of animation generally uses 24 frames.
Computers are being used more frequently to create animation. The main tool needed is some form of art or animation program. This can be a simple drawing program used to create the equivalent of cels for filming. This can also involve more complex programs for creating three-dimensional animation in what is known as computer generated imagery (CGI). CGI can produce full movies out of animation, and it is also frequently used in movies that mix animation with real live action. Computer animation can cut out the use of a camera, as one can immediately upload the images into a video editing program.
Clay is one of the main tools used for what is known as stop motion animation. Animators shape the clay into all of the characters in the story and place them in front of the camera. After shooting one frame, the director moves the clay pieces slightly and shoots another frame, using this process to simulate movement on video. Other objects like dolls, models and other toys can be used in this same fashion, but clay is the most frequent tool as one can mold it into the exact desired shape.
An animator needs the right type of camera to correctly film animation. The camera must be able to quickly start and stop to film one single frame. Many mini-cameras and even web cams have this ability. Because filming animation requires shooting one frame at a time in most cases, the filming process is very time consuming. A multiplane camera is one of the oldest forms used to make the process easier; the camera is built onto a special scaffold-like reel that moves the images in front of the lens while shooting to create the on-camera movement.