Working with White Balance
Working with White Balance
One of the “magic tools” of digital photog- raphy, white balance enables the photographer to control the ?ltering of the light with a button set on the camera. This is one area where shooting digital is vastly superior to ?lm.
Years ago, on assignment for a magazine, I used ?lm to photograph the president of a major railroad. I scouted the location as usual and found the conditions abysmal, to be polite. The main light source was faded-out sodium vapor lights. This required several gel ?lters over the camera lens to bring the source at least close to daylight, which reduced the exposure by several stops. Attempting to shoot on a slower speed ?lm wasn’t possible, because of the loss of light the gels created, so I had
to use a higher speed ?lm, with its inherent quality sacri?ce. Plus, I had to shoot Polaroids to check how he looked, and a lot of these folks give you a minimum of time. Now, if this had been on digital, I could have walked in, done a white balance by pointing the camera at a white card and pressing the WB button, and the camera would have neutralized the heavy o?-coloring of the sodium lights. Plus, I could have checked the image with the actual
photographs I was taking, not a Polaroid 45
simulation.
White Balance Can Be a Creative Tool
White balance is a very powerful child of digital technology that you can use as a creative tool, as well. In my ?lm days, I always had an 81A ?lter mounted on the front of all my lenses. This ?lter creates a slight warming e?ect, making many scenes more pleasant in their ambience. Now, if I’m shooting digital,
I put my white balance setting on 6000 Kelvin, which is also shown on most cameras as a setting to use on cloudy days. Thus, the little cloud that appears in my monitor tells me I’ve got the white balance set to a bit
of a warming “?lter.” Settings in the white balance area will also neutralize the greenish cast from ?uorescent lighting or the very orange cast from tungsten lighting, the most common lighting used in homes. The little icons for these settings show—you guessed it—a ?uorescent bulb and a regular light bulb. These manufacturers are on to something!
Note Kelvin, simply put, is the measurement standard for the temperature of light. The higher the temperature, the cooler or more blue the light. The lower the temperature, the warmer or more orange/yellow the light. Sometimes I like to shoot a daylight white balance under tungsten light because it imparts a warm, snuggly cast, like being at
home. Or I might shoot outdoors at dusk with the camera set on a lower Kelvin setting to emphasis the coldness of the evening with the extra blue this WB setting will provide.
46 White Balance Tips
White balance is our bag of ?lters in one simple button. I am always aware of the WB setting and have used it often for control or e?ect.
The following tips illustrate how you can capture more compelling images no matter what actual light is available:
¦ Don’t use the Auto white balance setting. This may provide an uneven response from frame to frame, as the camera—with even a slight shift of perspective—may establish its white balance from a di?erent “white” it ?nds in the frame. Also, since the purpose of white balance is to bring white back to true white, the beautiful “golden hour” hue may be removed from the photo!
Here are some typical color temperatures:
¦ Carry a white card or piece of cloth (or make sure you always wear a clean, all cotton T-shirt), so you always have a white sample available to take the reading from. If your white shirt has an optical brightener in it, it will ?uoresce under the strobe’s UV illumination. Just like white colors in a funhouse, the white shirt will glow bluish, but you may not notice it if you’re not in a funhouse dark environment (although it can balance your scene oddly). Consider pretesting your shirts under a UV source. I ?nd that a folded piece of white typing paper is
a practical thing to include in a camera bag. Use it folded to make it opaque, and photograph at least one image of this paper, shot in the same illumination in which you’ll ultimately shoot your primary captures.
Temperature Ambient Lighting Conditions
20,000+K High mountain open shade
9000–18,000K A blue sky (the higher your altitude, the higher the temperature)
6500–7500K An overcast sky
5300–5650K Electronic ?ash
5500K Daylight, around noon on a sunny day
5000–4500K Xenon lamp
3400–3600K “Golden hour,” one hour before sunset or after sunrise
4000K Warm white ?uorescent bulbs
2750–3000K A tungsten lamp, found in most homes (the lower the wattage, the lower the temperature)
3000K Early sunrise or late sunset
1500K Candlelight
Color temper ature measured in Kelvin (K)
47
These two photos, shot within seconds of each other, illustr ate how the photogr apher can
use the Kelvin setting as a filter. The photo at top was shot at a white balance setting of 3000 Kelvin, usually thought of as a tungsten setting. I wanted the intense blue cast, nor mally used to balance out the extreme war mth of tungsten, to create a mood. In the photo at bottom, I shot at the white balance setting of 6000 Kelvin to war m the photo slightly. 50–200mm lens, 1/125
second at f4
48 ¦ As mentioned, use the white balance as a warming ?lter or a slight cooling ?lter by dialing in appropriate Kelvin degrees.
¦ Use the custom settings on your camera if you intend to return to and shoot in an area that required an unusual white balance. This way, a twist of the dial will ready your camera immediately,
so you can come in from outdoors and resume shooting in that room that uses ?uorescent lighting.
¦ Get your white balance (and exposure) correct while shooting! Photoshop is a powerful tool, but the more you have to tweak the photo ?le, the more you will negatively impact the quality of the ?nal image. The old saying “garbage in, garbage out” holds true.
¦ Now, after the preceding discussion, let me emphasize the power of shooting raw ?les. Most mid-level DSLR’s on up are able to shoot raw and shoot it quickly. Without question, this ?le format provides the most power to the
photographer. See Jay Kinghorn’s Chapter 11 for a thorough discussion of raw.