White Balance and Color Theory

Essentially, white balance is concerned with the overall color of the light in which you are shooting. For example, light at the time of a dramatic sunset will have a distinctly reddish color cast to it. While interior lights, such as a certain incandescent lights can give off an orange glow. Our eyes are so good at adjusting for these color cast that we often aren’t aware of them, but for digital camera, unless the color of the lighting is addressed, whites will not appear in the capture image, hence the term “white balance“. In the case of sunset, whites will appear rossy pink, while in incandescent light, it will appear orange.

white balance

In photography, all light source are known as having a certain color temperature, color temperature is measured in degrees Kelvin. The most important thing to remember in Color Temperature is that the higher the Kelvin number, the cooler (more blue) the light source.

Why use the Kelvin scale as opposed to a standard white balance? If you can’t control the light tones of a room according to the standard “tungsten”, go Kelvin. If you can’t achieve the perfect skin tone of your subject by shooting on “cloudy”, once again, go for Kelvin.

Kelvin scale can also be used creatively for enhancing the colors of sunsets and sunrises. By altering and adding color with the Kelvin Scale, your images will achieve that “creative edge” with ultimate control.

Manual white balance

Although the exact procedure for a manual white balance varies somewhat from camera to camera (check your manual!), the basic procedure is similar. A white card is held up in such a way as to catch the key light for the scene–the light we want to be reproduced as white. The white card can be white typing paper, or poster board, or a commercially available card (Whibal Card) with white on one side and a test pattern on the other. The camera operator zooms in on the white card until it fills the screen, and then presses and holds the proper button to register a manual white balance until the indicator shows that the camera has set the temperature. Pro cameras will show the precise color temperature of the manual white balance in the viewfinder. Another professional way of doing this is through an Expo Disc, which you attach to the front of your lens.

The Color of Light

To reach us, light waves of color must travel from the sun and through our atmosphere, which acts as a filter. Because of the curvature of the earth, at sunup and sundown, these light waves must travel through more of our atmosphere than they would if coming from directly overhead at midday. As these light waves swim through our thick atmosphere, the shorter wavelengths on the cool end of the spectrum get lost in atmospheric dust and water and cannot reach us. This leaves the longer, warmer waves of light to penetrate our atmosphere and illuminate our subjects.
As the sun climbs higher into the sky, it shines more directly through our atmosphere, allowing the shorter, cooler wavelengths to reach us, better balancing the color of the light. On a clear day when the sun is directly overhead, it should exhibit no color when cast onto a white surface.

An often overlooked part of photography is choosing your color palette. Just like a painter, a photographer should be aware of the colors in a composition. Unlike a painter, a photographer does not have complete control over the colors of our palettes. When we shoot in a controlled environment like a studio we have much better control than when we shoot outside. Taking formal portraits of people (even outside) is also much easier to control than nature photography or street photography.

The color wheel can help you understand the colors in your composition better. The color wheel can be very basic (like the illustration with this article) or be very complex and show minute shading differences for millions of colors. The color wheel shows the relationship of each color to other colors. Colors next to each other are complimentary while colors across from each other are opposite colors. Colors that are at an angle to one another are often the most clashing colors. For example, purple and green do not go together well at all. Orange and green also fight against each other.

The stronger the color is, the more strongly the clashing effect will be felt. For example, a deep purple will clash with a deep green more strongly than a pale green and pale purple will clash.