Before I get into the definition of white balance, I want to give you a little background about why there is such a thing. Color temperature is a measurement used to determine the color of light. Different kinds of light cast a different color. For example, your everyday soft-white light bulb is actually quite yellow. Fluorescent lights have a greenish color to them and the suns color temperature changes depending on the time of day.

With film cameras, you had to buy film stock to match the color temperature of your lighting if you wanted natural colors in the photograph. With digital cameras, you can change the camera’s reaction to different light sources by setting the white balance. Most digital cameras offer basic white balance settings such as tungsten (typical household lights), fluorescent, and daylight. You may notice your pictures look very yellow when capturing indoors and not using the flash. Change the white balance to tungsten to get colors you’re more familiar with. The auto white balance setting only works well outdoors in the mid-afternoon sun.

To the right is an example of an outdoor scene lit by tungsten streetlights. The top picture was set to auto white balance and the picture below was set to tungsten white balance. Notice the yellow cast when the WB is set to auto. Because the white balance setting in the bottom picture matches the lights’ color temperature, the resulting colors are much more natural.