White Balance - The Definition of White Balance

White balance is a term referred to as the process of eliminating unrealistic color casts. White balance is also referred to the color tint of a photograph. White does not emerge as white whenever an image is shot under different light conditions.

Correct camera white balance needs to consider the color temperature of a light source. The color temperature is the relative coolness or warmth of white light.

An inaccurate white balance can cause an unattractive orange, blue or green color casts. These color casts are unnatural and particularly undesirable in portraits.

Color temperature is a term describing the light spectrum which is radiated from a so-called blackbody with that surface temperature. A blackbody can be considered as an object that absorbs all incident light and does not permit incident light to be reflected or passes through. Blackbody at various temperatures has different color temperatures of white light.

White balance also uses the green-magenta shift in addition to color temperature since some light sources does not resemble blackbody radiations. Under ordinary daylight, the green-magenta shift is sometimes unnecessary. On the other hand, significant green-magenta adjustments to the white balance may be necessary when using fluorescent and other artificial lighting.

Source: AZoOptics