Since the Renaissance, scale has become an integral part of visual literacy as a whole. Scale in an image, like a scale in a produce market, acts to show relations between objects. Rather than measuring weight, however, visual scale deals with apparent relative size of objects. By manipulating the apparent size of objects, scale can be used to produce a number of effects. Manipulation of scale can give greater meaning to a basic image, lending it new life.
Scale is most commonly used in order to create the illusion of depth on a two-dimensional plane. The pioneer of this technique was Raphael, a Renaissance artist whose works introduced the concept of using scale as creation of depth to the Western art world. The basic principle behind this technique is that objects diminish in apparent size as they approach the horizon. Artists over the centuries have adopted this technique as a standard for representing depth in painting, photography, and film.
Since the dawn of film, the use of scale has been further developed. No longer is scale restricted to the creation of an illusion of depth, but may be used to give information in the form of visual communication, concerning the characters and relations between them. The positioning of characters and the scalar relationship between the two reveals, without dialogue, the relationship between characters, as well as defining traits of a character or characters.
Finally, scale may be used to create an emotional response in the viewer. By clever use of scale, the director may manipulate the feelings of the audience in order to invoke a stronger relationship between the characters in the film and the viewer.