Understanding White balance and how it affects color in your digital photography.
In film days, a photographer might have a whole range of colour correcting filters in his bag, ranging from amber coloured filters to warm up the image, to blue filters to cool it down. Although they could be used for adding a special effect, most of the time these filters would be used simply to adjust for the color temperature of the light, so that the result would look natural to the viewer’s eye.
Now with digital photography, these filters are mostly redundant, and adjustments for the color temperature of the light can be done via the camera’s white balance menu.
Firstly, what does adjusting for the color temperature of the light mean?
Different types of light – tungsten, fluorescent, daylight, and so on – have different color temperatures, and even within the one category of daylight, the color temperature will vary considerably depending on the time of day and the prevailing weather conditions.
Our eyes and brains adjust for the different colour temperatures, so that unless we really stop to think about it, we see all light as much the same. The camera however will accurately record the temperature, so that a photograph may take on an unnaturally warm (red) or cool (blue) cast.
We've all seen digital photographs taken indoors without flash, under tungsten light – they have an almost orange tint to them, due to the warm color cast caused by tungsten light.
A digital camera’s white balance menu will offer an Auto option, which usually does a pretty good job of evaluating the light and giving a reasonable result. However, if you become familiar with the other white balance settings, you can be more certain of getting a natural looking photograph with no undesirable color cast.
In digital photography, the color temperature of light is measured on the Kelvin temperature scale (K).
In addition to Auto, white balance menus will usually include some or all of the following options:
Incandescent (3000K) Use with incandescent lighting, which includes tungsten and most household light bulbs.
Fluorescent (2700 – 7200K) There is a wide range within this category depending on the type of fluorescent lamp. Your camera may offer a range of different settings for fluorescent light.
Direct sunlight (5200K) Use when your subject is lit by direct sunlight.
Flash (5400K) Use this setting when you’re using the camera’s flash.
Cloudy (6000K) Use this when you’re photographing outdoors under overcast skies.
Shade (8000K) Use this setting when your subject is in the shade on a sunny day.
In addition to the above, your camera may have an option to choose the color temperature according to a precise Kelvin scale value, and also a pre-set option where you can record and save a white balance setting to use under a particular light source. The setting is obtained by photographing a neutral grey or white object under the light source that is to be used in the final photograph.
If you would like to improve your digital photography skills and learn more about color and how white balance affects your images, why not sign up for Phil Malpas's Capturing Color Course or Jim Low's Course on Architectural Photography