Digital Camera Master

Different light sources, such as tungsten light bulbs, produce light at different color temperatures than normal daylight (different temperatures often result in pictures that are “cooler” or “bluish” in some situations, or “warmer” or “reddish” in others). Your optical/nervous system compensates for these variations in color, but cameras need a little help as you move from outdoors to indoors.

Film cameras rely on color correction filters to capture natural tones under a variety of conditions. Digital cameras make things easier by providing a built-in white balance adjustment. This control not only allows you to capture pictures with accurate tones, but also enables you to preview the effect on your LCD monitor before you take the shot. Think of the white balance control as your own personal filter collection, built right into the camera.

The default setting for your camera is auto white balance. This mode works amazingly well most of the time. To test for yourself, point the camera at a different light source, such as a regular light bulb, and watch in the LCD monitor as the image slowly goes from very amber to a less surreal off-white.

Still, the effect produced by auto white balance may not always be exactly what you’re looking for. In these instances, you can override the auto mode via one of the color correction presets available on your camera. Here’s a list of the most common ones:

1. Daylight
Used for general outdoor photography. Adds slight warmth to the coloring to offset a blue, cloudless sky.

2. Cloudy
Helps correct overcast skies, but is also good for shooting in open shade, such as under a tree. This setting adds more warmth to the scene than the daylight selection.

3. Tungsten
Adds a bluish tone to offset the reddish cast created by standard light bulbs.

4. Fluorescent
Corrects for the greenish cast under warm-white or cool-white fluorescent tubes.

5. Fluorescent H
Helps balance the color for daylight fluorescent tubes.

Figure below shows a typical white balance menu. The Cloudy white balance setting warms (adds red/yellow to) the tones in the picture. The Tungsten setting (represented by the light bulb to the right of Cloudy) cools (adds blue to) image tones.

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Many intermediate to advanced cameras also include a custom white balance that allows the camera to find the right color correction when you point it at a white surface. Even better, some advanced digital SLRs, such as the Canon 20D, let you select specific hues via the Kelvin color temperature scale.

One final thought on white balance: if you use the RAW format when capturing images, you can stick with the auto white balance setting, then fine-tune the color temperature later on your computer with the RAW image editor. I wouldn’t recommend this technique as your default approach, but it is helpful in tricky lighting situations when you’re having a hard time determining the right camera setting.