Eliminate color casts

Accurate exposure, faithful color, and sharp focus are the technical cornerstones of good photography. Of the three, color is the most often overlooked—many indoor shots end up with a dark reddish tint, while many outdoor snapshots end up blue and lifeless. But there’s plenty you can do to avoid these problems—even if you’re using a basic point-and-shoot digital camera. The key is understanding your camera’s white-balance settings.

Of digital photography’s many blessings, the white-balance menu is near the top of the list. Back when I was shooting on film, I needed several filters to help me capture semi-accurate color. Every time lighting conditions changed, I had to stop, dig out the appropriate filter, and attach it to my lens—assuming, of course, that I hadn’t left it in the pocket of a different coat the last time I was shooting. And after all this fussing, I was still often disappointed with the results.

Digital cameras eliminate the need for color-balancing filters by providing white-balance settings. Even a camera’s automatic white-balance setting is often more accurate than the elaborate combination of filters I used in the past. But it isn’t always perfect. Just as your camera’s light meter can be fooled in certain shooting conditions, so can its color-measurement system. In these cases, you’ll need to take advantage of some of your camera’s other white-balance options.

Learning to see the light

Different light sources produce light at different temperatures. The light from a typical desk lamp is about 2900 Kelvin. A neon bulb, by contrast, is around 6000 Kelvin. As light’s temperature changes, so does its color. Higher temperatures produce cooler (bluish) tones, while lower temperatures produce warmer (reddish) tones. Our optical system adjusts with the light, providing us with a remarkably consistent view of the world. Cameras, on the other hand, have more trouble adjusting to their surroundings.

Your camera’s automatic white-balance setting is calibrated for photographic daylight (5500 Kelvin). But the color temperature around us is always in flux. The minute high clouds appear in the sky, for example, the light jumps to around 8000 Kelvin. If your camera fails to recognize the temperature change, your photo will take on a bluish tint—making skin tones appear somewhat lifeless. If you move indoors, where your main light source is a 100-watt incandescent bulb (which measures at around 2900 Kelvin), your picture will most likely have a very orange cast. Your camera can also become confused by scenes dominated by a single color, such as a broad green field.

To compensate for such situations, digital cameras offer a variety of white-balance settings (represented by icons), which work like traditional color filters, warming up or cooling down a scene as needed. For example, the cloudy setting (represented by a cloud icon) is the digital equivalent of a warming filter and is perfect for warming up skin tones on an overcast day. Likewise, the tungsten setting (typically given a light-bulb icon) acts as a cooling filter, compensating for warm indoor lighting.

Many cameras include additional white-balance settings that offer subtle variations on the tungsten and cloudy filters. For example, shade and flash settings both act as warming filters (the color temperature of light in open shade is 9000 Kelvin, while an electronic flash is 6000 Kelvin). The warming effect of these settings tends to be more powerful than the cloudy setting—in fact, it’s often a little too strong for my taste. A sunset setting, on the other hand, cools colors (it produces a stronger effect than tungsten). That’s because the light at dawn and dusk is usually very warm, around 2200 Kelvin.

Once you understand how your camera’s white-balance settings work, you can use them to creatively con-trol an image’s tones. For example, you could emphasize loneliness in an outdoor portrait by switching to the tungsten setting, thus giving your photo cool bluish tones (see “Creative Color”). When shooting at high altitude, where the light can be very bluish, you might consider switching to the cloudy setting to warm up the tones in your landscape, even if there’s not a cloud in the sky.

Customize your white balance

If you’re having trouble finding the correct white-balance setting, or if you’re shooting in a particularly challenging location—museums, for example, often use halogen lights, which most cameras don’t offer an option for—you may be able to have the camera do the hard work for you.

Most digital cameras offer a custom white-balance mode. When you activate this mode, your camera measures the current light temperature and creates a precise white-balance setting to match it. The camera will preserve that custom setting until you switch to another white-balance mode. Technically speaking, this is an extremely sophisticated feat, but creating a custom white balance is relatively easy. In fact, there are a few ways to go about it:

White Sheet of Paper Position a white sheet of paper so that the dominant light source reflects off it. Select your camera’s custom white-balance setting, make sure the paper fills the frame, and then press the shutter button.

Coffee Filter Although the white-paper method works well, sheets of paper tend to flop around, so they can be challenging subjects.

An easier option is to use a coffee filter. Select the custom white-balance setting, hold the coffee filter over the camera lens, and point your camera toward the dominant light source. I recommend turning off your camera’s autofocus mode when you use this technique, so you don’t drive the focusing system crazy. (If you have a compact camera, set the camera to infinity mode.) When you press the shutter, the camera will calculate the appropriate white-balance setting.

ExpoDisc For people willing to spend a little money to get accurate color from a camera, I find that the most convenient option is the stylish ExpoDisc, by ExpoImaging. This calibrated filter snaps onto the front of your lens, for highly accurate, hands-free white-balance measurement. It even comes with a neck lanyard, so the filter’s always handy while you’re working. ExpoDisc prices range from $100 to $200, depending on the size (if you don’t want to buy multiple versions to match each of your lenses, get an ExpoDisc that covers your largest-diameter lens and then simply hold it in front of your other lenses).

Fixing your white balance with the ExpoDisc is similar to using a coffee filter. Choose the custom white-balance setting, attach the filter to your lens, and point it toward the light source. Remember to turn off the autofocus when you’re taking the reading, and then turn it back on once everything is set.

Back to the beginning

Even if you’re shooting in the Raw format, you should try to capture accurate color. By spending a few seconds adjusting your camera, you can spare yourself a lot of postprocessing work.

And no matter which technique you embrace, once you’re done shooting, return to the automatic white-balance setting. It’s the best choice when you need to grab a shot in a hurry.

Which fluorescent?

You may notice two white-balance settings for fluorescent light: Fluorescent and Fluorescent H. This is because not all fluorescent bulbs produce the same type of light. Typical warm-white and cool-white fluorescent bulbs tend to produce a greenish cast. For these, you’ll want to use the Fluorescent setting. Some newer fluorescent tubes are balanced to better simulate daylight. For these, the Fluorescent H setting will probably provide better results, because it’s more closely matched to the fluorescent daylight spectrum.

How do you tell which type of tube is which? Just look at your skin tones while standing in the room. Your skin will look more natural (and just plain better) under daylight-balanced tubes than under standard fluorescent light.

[ Derrick Story is a professional photographer, author, and teacher. For more photo tips, listen to his podcast. ]

One Shot Three Ways: When you’re shooting in the shade, the camera’s automatic white-balance setting can result in an image that’s a little too cool (left). By switching to the cloudy setting, you can warm up those skin tones—perhaps a bit too much in this case (center). The most accurate approach is to create a custom white-balance setting (right). I used the ExpoDisc, but a sheet of white paper would have worked, too.Creative Color: White-balance settings are useful for creative purposes, too. When taking this photo, I used the tungsten setting to convey a somber mood.

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