How the Camera Works

Basic Camera functions

In order to understand the camera more fully, lets break it down to its essentials. The camera is basically a light-tight box that contains a light sensitive device (sensor). The camera also has an opening that allows light into the box to provide "exposure" of the sensor which inturn creates an image. In front of the opening is a lens that "focuses" light onto the sensor in order to create a sharp image.

There are three main controls on the camera that are essentially designed to control how much exposure to light the sensor receives. The precise amount of exposure is crucial in order to create a discernable image. The three main controls are:

Aperture: This is an adjustable opening that lets in various amounts of light by channging the size of the opening or aperture.
Shutter: This is like a curtain that opens and closes and lets light through to the aperture for a specified duration.
ISO: This adjustment controls how sensitve the sensor is to light and therefore can change how effective the other two controls are at controlling exposure.