White Balance, as defined by cambridgecolor.com, is the process of removing unrealistic color casts, so that objects which appear white in person are rendered white in your photo. Remember the lesson about how white light is composed of all the colors of the visible spectrum? Well, different light sources tend to have a characteristic tint. For example, normal daylight white flourescent lights cast a greenish light, sunsets cast a yellow-orange light, etc. This is called the “color temperature” of the light source. This works on the idea that light sources have relative “warmness” or “coolness” (see table below).
While our eyes have no problem adjusting white balance given a certain “color temperature”, digital cameras do. That’s why in a scene where there are different light sources, or where there is no white-colored object, the digital camera may capture the same scene with different color tints.
Preset White Balance Settings
Most digital cameras have the following preset values for coping with White Balance:
- Auto – This lets the camera make its “best guess”. Remember though that without a white colored object in the frame, you could take different shots of the same frame (same subject and lighting), and wind up with shots with different tints.
- Tungsten – This mode is used when the light source is an incandescent light bulb.
- Fluorescent – This mode is used when the light source is fluorescent light. Please note that modern flourescent lighting (especially compact flourescent lights) come in several “tints” (e.g. daylight white – 6,500K, cool white – 4,200K, and warm white – 3,000K), making things a little tricky.
- Daylight/Sunny – This mode is used for outdoor, sun-lit shots; “normal” shots.
- Cloudy – This mode is used, as the name implies, for cloudy outdoor shots.
- Flash – The camera’s flash normally casts a bluish tint. This mode shifts it towards the reddish side to give a warm feel.
- Shade – Useful when you’re shooting in the shade.
You may also purposely try different White Balance settings for that “creative effect”. For example, I tried shooting the full moon using the different White Balance settings on my Pentax K-x.
With the Tungsten setting, a Blue Moon need not be a rare occasion.
Here’s another set of shots I took of a restaurant in the Ayala Triangle area.
So far, you’ve seen how the different White Balance settings affect the tint of the picture on night shots. What about in daylight? Well, the difference is less pronounced but still obvious. Here’s a shot of the museum wing of the Cathedral of San Jose, Batangas originally taken in Auto White Balance (AWB). I did some post processing using the Pentax Camera Utility using Daylight, Cloudy and Shade White Balance Presets.
I hope you see the effect of White Balance is on the overall “tint” of the picture.