Chapter | 3 |
Photographs are taken by the agency of light travelling from the subject to the photoplane in the camera. This light usually originates at a source outside the picture area and is reflected by the subject. Light comes from both natural and artificial sources. Natural sources include the sun, clear sky and clouds. Artificial sources are classified by the method used to produce the light, including burning, heating, electric sparks, arcs or discharges and luminescence. Light sources differ in many ways, and the selection of a suitable source is based on a number of significant characteristics.