Your camera comes equipped with a very useful and creative tool, the white balance button (WB for short). The white balance makes things that are supposed to be white really look white. Normally, if white things look white, all the other colors look right, too. Your eyes and brain make this adjustment automatically: White paper looks white under sunlight, shade, or a desk lamp. But you have to tell your camera to make the paper white under each different source of colored light (FIG. 4.9).
Fig 4.9 The feathers on this female willow ptarmigan are just starting to change to winter white. Only the white breast gives the bird away against the colors of the tundra. We were in thigh-high plants, and this adult popped out of hiding just a few feet from us. She posed for us for a few seconds and then disappeared into the bushes. Denali National Park, Alaska. (Nikon D2X, ISO 200, 200–400 mm lens, tripod, 1/400 sec. @ f/4.)
Pushing the white balance button presents plenty of choices: Automatic white balance is followed by a series of presets showing little icons of a tungsten lamp, a fluorescent lamp, a sun, a little lightning bolt (indicates flash), clouds, and the shady side of a house. Your camera may also offer a few manual settings. Consult your camera manual for the actual Kelvin temperatures of these presets (FIG. 4.10A–F).
Fig 4.10 A–F This series shows a marmot shot with various white-balance settings. Since the marmot wouldn't sit still while I changed my white balance in-camera, I set the white balance during processing, using Adobe Camera Raw to match the color temperature that my D2X camera would apply for each white-balance setting. Some of the changes are subtle; it's all about getting the camera to see what you see. If you shoot RAW, you can make these changes in processing; if you're shooting JPEGs, you'll want to make the adjustments in the camera. Sequoia National Park, California. (Nikon D2X, ISO 320, 70–200 mm lens, tripod, 1/400 sec. @ f/3.2.)
Couldn't you just use the automatic white balance all the time? You can do that, and it will probably work fine most of the time. But most cameras' auto WB only ranges from 3000–7000 degrees Kelvin, and light has a wider range of color than that. Auto WB works by measuring the reflected light from the subject—not by measuring the light itself. But reflected light can have lots of different colors, especially if it's coming from something very colorful. Auto WB looks at all these colors and tries to make white look white. Sometimes this system works, sometimes not. I'd rather set the white balance myself most of the time; after all, I want the photograph to look the way I see it, not the way the camera sees it.
Most DSLR cameras have a variety of ways to set white balance manually. You can dial in a specific Kelvin temperature, choose one of the presets, or use a custom white balance. A custom white balance is usually set using a white card, but anything white will work. Put whatever you're using to set the white balance in the same light as the subject you're shooting. If you're photographing a flower in the shade, your white card needs to be next to the flower in the same shade. If it's a sunny landscape, the card has to be lit by the sun. Fill the viewfinder with the card, push the custom white balance button, and your subject is properly white-balanced in that light. If the light changes, you have to perform the steps again. You don't need to buy anything—just use a piece of white paper. I use commercially available cards from WhiBal (PictureFlow LLC) or one of the plastic "warm cards" from Vortex Media (FIG. 4.11 and 4.12).
Fig 4.11 I used the daylight preset white balance for this image. Little spots of direct sunlight hit the water, and the daylight preset kept the water pretty neutral. Accurate, but not very creative. Limekiln State Park, Big Sur, California. (Nikon D100, ISO 200, 28–70 mm lens, tripod, 1/5 sec. @ f/8.)
Fig 4.12 Without moving the camera or changing the exposure from , I switched the white balance to the tungsten preset. Wow, I like it! The water looks totally different—more like it felt when standing in that cold creek. Limekiln State Park, Big Sur, California. (Nikon D100, ISO 200, 28–70 mm lens, tripod, 1/5 sec. @ f/8.)
If you're shooting JPEGs and want the best possible quality, get your white balance right when you take the picture. Try a custom white balance, as I just discussed. Trying to fix the color in JPEGs after shooting isn't a good idea. Every time you make a computer adjustment to a JPEG image, you lose data, so it's important to get the image right while it's in the camera. If you shoot RAW, you can fix color-balance problems later, when you process the images. Of course, that's one more thing to fix at the computer.