Photographers often deal with a variety of light sources, each of which has it’s own color cast. When compared to daylight in the middle of the day, tungsten lighting, like that which comes from traditional incandescent bulbs, looks yellow. Standard fluorescent lighting looks green. Light in shade, or on a cloudy day will have a bluish cast compared to midday sun. These color casts are referred to as the color temperature of the light. Color temperature is measured in degrees Kelvin. To beginners, color temperature will appear to be a bit backwards. From 2000°K to about 3000°K are warm tones, and above 5000°K are cooler tones, getting progressively more bluish as the color temperature goes higher. Midday sun tends to be at around 5500°K – 6000°K, while the sun at the horizon is warmer, at about 5000°K. Overcast daylight will be around 6500°K, and shaded daylight will be around 7000°K.
Thankfully, today’s digital cameras have a tool to correct for the different color casts created by the various light sources we encounter. For beginners, using the Auto White Balance setting is an excellent start. The camera will try to neutralize the color cast caused by different light sources and give the image a pleasing balance. However, while a neutral color balance is often desirable, there are times when as artists, we may want to use the white balance tool to creative effect.
You can choose what kind of mood you want to set before shooting if you like, by choosing a preset white balance. Most cameras offer Auto, Daylight, Cloudy, Shade, Fluorescent, Tungsten, Flash, Custom, and Kelvin temperature white balance settings. These settings will neutralize the color cast from the light source they are designed for. For instance, Fluorescent neutralizes the greenish cast given off by fluorescent light. Custom white balance is a user defined setting where you tell the camera what in the scene should be white, and the camera corrects to make it so. Finally, the Kelvin white balance setting allows you to choose the color temperature of the light source you are shooting in. If you choose to use the presets in lighting other than what they are designed for, your image will be warmer or cooler, depending on your setting and the available light.
For all of those settings, the camera is simply looking to make white look white. While that may be what you want, by intentionally setting a different white balance, you can add to the mood. Choosing Shady or Cloudy white balance will warm up your image, and choosing tungsten will cool your image. This type of thing is done constantly in movies and television shows to help set the mood. Photographers as well choose their white balance to set the mood. A cooler color cast gives the image a colder, harsher feel, while a warm color cast is generally seen as inviting.
If you shoot only JPEG, you’ll be stuck with whatever white balance you had selected at the time of shooting, so if you want to change the mood by adjusting your white balance, you’ll have to choose to do this beforehand. However, if you shoot RAW, the white balance can be adjusted after the fact, using whichever RAW converter you choose. You’ll be able to choose from the presets that are loaded in the camera, click in the image to determine what color should actually be white, or you can simply select Kelvin white balance, and using a slider, adjust the white balance in degrees Kelvin and see what the different color temperatures look like.
By taking control of the white balance, you give yourself another tool that can alter the mood of your images and allow you to better communicate what you want to say with your image. Not every image will benefit by shifting the white balance setting, and there will be some photographers who will be adamant that you should always shoot to the “correct” white balance. As the artist, this is your time to exercise your creative license and do what feels right to you.