Click to explore how the white balance setting affects the way images are captured.
Fluorescent light has a variety of color temperatures depending on its type. Some bulbs are daylight balanced.
If you place a gray card in a scene, you can use it later to remove color casts and apply the settings to other photos taken under the same light.
One way to eliminate white balance problems is to use flash since it has the same color temperature as daylight.
Typical white balance icons (clockwise from top) are auto (AWB), manual, flash, fluorescent, tungsten, cloudy, shade, and daylight.
Click to explore how sRGB and Adobe RGB color spaces compare when it comes to the number of colors they can capture.
Although light from the sun or from a light bulb looks white to us, it actually contains a mixture of all colors, all of which affect the color of a scene it illuminates and the photos we take of the scene. We normally don't see the subtle differences because our brains compensate automatically. However, we do notice extremes as when the rising or setting sun casts a warm red glow over everything it illuminates. The color of the light you shoot in is specified by its color temperature in degrees Kelvin, somewhat like the room temperature is specified in degrees Centigrade. As color temperature increases, it moves through the colors red, orange, yellow, white, and blue white in that order.
Daylight contains proportionately more light toward the blue end of the spectrum. Incandescent light contains more toward the red end.
"White" light actually contains light of different colors. The overall color cast of the light changes as the proportions of the colors change.
You can check white balance by looking at a captured image on the camera's monitor to see if white areas in particular have some color cast to them. (You may want to zoom the image so you can see enlarged details more clearly). To remove color casts and capture images with colors that look like they were shot at midday, you use the camera's white balance system. This system automatically
or manually adjusts the image so colors are captured the way we see them regardless of the light illuminating them. For example, the fluorescent setting compensates for the greenish light from fluorescent lamps and the tungsten setting compensates for the warmer, more reddish color of tungsten
If your camera lets you use the RAW format (page 50) you don't have to worry about white balance settings until later, when you are editing the picture. The camera will use the current setting for the preview image, but the actual white balance can be selected during editing. This lets you try different white balance settings until you find the one you like best.
Many digital cameras offer a number of white balance settings, some for specific lighting situations.
- Auto (the default) works in a wide variety of lighting conditions.
- Daylight is best when photographing outdoors in bright sunlight. When photographing indoors, if you like the warm glow of incandescent lights, you can capture them with this setting.
- Cloudy is best when photographing outdoors in cloudy or overcast conditions.
- Incandescent or tungsten is best when photographing indoors under incandescent lights.
- Fluorescent is best when photographing indoors under fluorescent lights.
- Flash is best when photographing with flash. In fact, flash is daylight balanced so it's an ideal way to remove color casts in some lighting situations.
- Color temperature lets you select a specific setting from the Kelvin scale. In a studio, where you know the color temperature of the lights, you can set the camera to an exact match. In other settings you can use a color meter to determine the setting you should make.
- Manual or custom lets you set white balance manually by aiming the camera at a piece of white paper or gray card.
White Balance Bracketing
Some cameras let you bracket white balance by processing a single image into three pictures with different color tones. One image is processed at the set white balance, the second with a blue or magenta bias and the third an amber or green bias. You may also be able to specify the amount of bias in each direction.
In addition to controlling white balance, some cameras also let you change the color space used to capture images from the default sRGB to the wider gamut Adobe RGB color space. sRGB, which supports fewer colors, is the default color space in almost all digital cameras. Although suitable for images that will be displayed on a monitor, when editing images and making high-quality prints, Adobe RGB is a better choice if your camera offers this option.