Can you please give me a good defintition for "white balance".

I know that many digital cameras speak of automatic white balance but I have yet to be able to find a good definition of what white balance is.

Thanks!

-- john goode (john_goode@hp.com), November 06, 1998

Answers

Our eyes have a remarkable ability to adapt to different colors of illumination, perceiving "white" as "white," under an incredible range of lighting. If you want to see just how far from "white" some lighting is, take a picture with standard color slide film (daylight balance) under tungsten incandescent lighting!

Digital cameras (and most video cameras) try to mimic our eye's ability to compensate for different lighting coloration by balancing the lightest portion of the images to a neutral white. (Hence the name "white balance.") How well or poorly they do this will vary depending on the camera, lighting type (incandescent, fluorescent, daylight, etc), and the exposure level. The standard test shot we take indoors under incandescent lighting gives a a good indication of how well cameras' white balance works under decidedly "non-white" conditions, but it is only a single data point (so don't place *too* much faith in it).

Some cameras provide only automatic or preset white balance, while others allow you to select from among a number of presets, such as daylight/sunny, daylight/cloudy, incandescent, fluorescent, etc.

-- Dave Etchells (web@imaging-resource.com), November 06, 1998.