Want to take pictures like this?
Then you’ll need to master the art of exposure – controlling the amount of light which enters your camera.
What is exposure?
Like the eye, cameras operate by recording light when it strikes a sensor in the camera. The camera’s sensor is made of a grid of semiconducting material (the number of light-sensing “buckets” in this grid determine the resolution of the photograph). When light strikes a “bucket”, the incoming energy frees paired electrons in the material, causing an electric current to flow. This electricity is picked up by a processor in the camera (its “brain”) and the responses from the “buckets” are compiled to form an image.
The amount of light striking the sensor while the camera’s shutter is open determines how much light is recorded in the image. In other words, the more light that enters the camera (or the longer the camera is exposed to a constant source of light), the brighter the resulting image will be. This is called the exposure.