Sources of light vary in degrees of color temperature. For example, fluorescent lights are cooler and green, while incandescent lights are warmer and orange. The color of an object will reflect these cooler and warmer tones when viewed under different light sources. The chart below shows the color temperature of different light sources in degrees Kelvin (K).
The human brain naturally processes these differences in color temperature to keep a “white” object appearing white to our eyes under different lighting conditions. However, digital cameras need to be told what “white” looks like under different sources of light. In the camera's white balance menu, you’ll find preset adjustments that add warmer or cooler tones to your image. Here is a list of some example presets and the types of tone they add to the image.
You can use the camera’s preset options to adjust the color temperature of your image. For example, the images below move from a cooler tungsten preset, to a neutral automatic white balance setting, to a warmer preset.
The auto white balance setting gives a fairly accurate representation of how the color white should appear in the image. However, you may want to use manual settings to achieve the most accuracy, or to achieve a desired stylistic effect.