Photography : Animation Basics

In the field of traditional photography, much effort has been expended toward the goal of producing sharp images of fast-moving objects. In the field of animation, the opposite problem arises. If each frame in a sequence depicting a moving object portrays the object as a sharp image, then the motion may appear jerky. However, sharp images are a natural byproduct of creating frames as individual images of stationary objects in a screen graph.Thus, animators often artificially distort the image of a moving object in a computer-generated frame. One technique, called supersampling, is to produce multiple images in which the moving object is only slightly displaced and then to overlay these images to produce a single frame. Another technique is to alter the shape of the moving object so that it appears elongated along the direction of motion.