What the heck is "White Balance" anyway?

If you take pictures, you've heard the term "White Balance". Maybe you saw it in the instruction manual of your digicam, or in a post about photography. But what is it? Simply put, it is how white white is; if you pointed your camera at a truly white object, how accurate would the picture be? This is important if you take pictures of graffiti, which are often shot outdoors and sometimes at night. Amy Renfrey from www.DigitalPhotographySuccess.com
wrote a little piece about the subject which she has allowed me to post here:

Understanding White Balance

In digital photography terms, and traditional, you will most likely hear the term “white balance” quite a lot. It’s an important meaning because many digital photography enthusiasts concentrate on the lenses and digital camera without first learning about how light works.

In a nutshell, “white balance” in digital photography relates to the ‘temperature’ of light. If you notice when doing your digital photography indoors, the photo will have a bluish colour through out the digital photo. Then if you take your digital photography outside you will notice the photo then has a warmer tone to it. This is your white balance feature on your digital camera working to adjust the image.

To give you a direct example of how white balance works in your digital photography think of this; have you ever noticed how your colour pictures come out a more bluish tone in the shade? The problem is that because light has temperature, the camera has to analyze this change in its own limited way compared to the human eye.

You can help reduce the blue by altering the setting on the camera or adding a warmer color filter such as yellow. Some colour filters have different shades or hues of the same colour. Each warmer colour filter moves towards a warmer feel and increases in density.

Your white balance in digital photography also works when you walk into an office building. The fluorescent light might be different from that of the doctor’s or a drug store? Well, you’re not imagining things! The reason is there are over 40 different ranges of fluorescent lights and the problem for us digital photographers is that each one has its own colour temperature. It’s not to be avoided, please no! It just means you need to be aware that all florescent lighting is not the same and that you’ll have to consider this when shooting under this type of light.

You can work well with white balance by switching indoor shots to an “outdoor” setting to eliminate the bluish tone in indoor shots. And alternatively you can set the white balance mode to “indoor” when you are outside to reduce some golden/yellow saturation in your outside digital photography shots.