What Is A Lens Camera?

Basically a camera consists of lightproof box with a lens system in front and photographic film at the back. The lens system, which converges light onto the film, consists of a number of lenses. The purpose of using more than one lens is to minimise defects or aberrations of the image. Objects at different distances are focused on the film by moving the lens system. Like the pupil in the eye, a camera also has an opening or aperture, whose diameter can be varied by the camera iris. There is a shutter placed between the lens system and the film. When a photograph is taken the shutter opens and closes rapidly. The time for which the shutter remains open can be adjusted.