The motion picture industry uses many terms and specialized equipment that are not used anywhere else. To perform their duties as a Camera Assistant, camera assistants' need to be aware of these terms and the basics of cinematography along with the names of specific pieces of equipment. The two primary film formats used for shooting filmed productions are 16 mm and 35 mm. When using film, almost all professional cinematography is shot using one of these two formats. A new type of light meter has been introduced that is becoming quite popular among Cinematographers. For professional cinematography, proper color reproduction of objects in a scene is dependent on the color temperature of the light source used to illuminate the scene. In addition, a Cinematographer may want to change the exposure of a shot without affecting depth of field, and this can be achieved by changing the shutter angle.