ABSTRACT
All principles of optics and optical design are based on a few properties of physics. The two most basic are reflection and refraction. There are a few things the cinematographers need to know about the basic behavior of light in order to understand the fundamentals of optics. The refraction of visible light is an important characteristic of lenses that allows them to focus a beam of light onto a single point. Refraction, or bending of the light, occurs as light passes from one medium to another when there is a difference in the index of refraction between the two materials. By shifting the focus of the lens, or by stopping down, or using a wider angle lens, the cinematographers can bring them into focus, but let’s assume the cinematographers are shooting wide open with a fairly long lens. For every focal length and f/stop, there is a particular focus distance that is special: the hyperfocal distance.
