White Balance or Color Balance Setting
The white balance (WB) setting on your camera sees the principal light source as white light. In color photography this is especially important, as every light source is different and has a characteristic color. Each light has a color temperature (measured in degrees Kelvin). When your camera sets the WB, it sets it to the color temperature of that light.
Most people have seen photographs taken indoors that were very orange. This happened because the WB setting was set incorrectly and the house lamps (known as incandescent or tungsten) caused the picture to become orange. By changing the WB setting correctly, the camera would have seen and recorded the orange light as white light and the picture would have looked normal.
You've probably heard the expressions
Normally the human eye compensates for different lighting conditions and we are not aware of differences in the color of light. Most digital cameras automatically adjust for the correct color temperature. However, there are times when you will want to override the automatic setting or even set the WB to a wrong setting for a special colorful effect.
If the balance is not too far off, it is easy to compensate for color balance of a digital image by using image-editing software. However, you will suffer some loss of definition during the editing process.
Color temperature is measured in degrees Kelvin. For instance, a 100- watt incandescent bulb measures 2,850° Kelvin, noon light measures about 5,500° Kelvin, and average daylight is approximately 6,500° Kelvin. Higher temperatures such as daylight are bluer, and lower temperatures such as house bulbs are red or orange.
Here are some typical settings you will find on mid-level cameras:
Shade — outdoors
Fluorescent Light — Daylight
Fluorescent Light — Warm White
Fluorescent Light — Cool White
Some high-end digital cameras allow you to override the automatic color balance system. Why would you want to adjust the color balance manually? You do this because you can sometimes achieve a desirable effect. For example, say you're shooting a candlelit dinner scene. By overriding the color balance feature, you'll be rewarded with a moody image exhibiting a warm glow. In other situations, the color balancing system does not remove all unwanted colors. By choosing a different color balance setting you may be able to correct such problems, making colors appear truer.
Many cameras allow you to zoom into a subject — say a person's face — set the color balance, and then zoom back. A custom setting will be more accurate than trying to set the white balance for the entire scene, which may be a mix of light. In this example, since the person's face is what you care about, you can tailor the lighting for the best effect.