What is White Balance?
White balance is a correction of the picture data that a camera’s image sensor has recorded. It adjusts the color rendition to the the light under which you have taken the picture.
It is a shift of color tones and is not related to how pale or bright your colors look.
The term „white balance“ originates from the fact that this correction is best done by using a neutral white or grey area and „balance“ color rendition so that this reference is rendered neutrally. A „correct“ color rendition lets such a reference area appears with exactly the same levels of red, green and blue in the final image.
White balance is necessary because the human brain adjusts color perception continuously. The light emitted by a photo subject varies a lot more under different lighting conditions than human perception recognizes it.
Example: Freddy is sitting in candlelight and the picture of her is taken with a white balance setting for daylight.
The color rendition is very orange because the candlelight has a higher share of red light than the sun. We humans also perceive candlelight as warmer than normal daylight but not as much as on the picture.
Accordingly the white balance does not always aim for a „correct“ color rendition, it can also be adjusted to get a „natural“ color rendition, i. e. color tones close as possible to human perception.
And you can go one step further to manipulate color rendition as you would like to have it for a certain effect of your image, mainly towards warmer or cooler colors.
Here an example, Freddy has now switched on electrical light above the table:
The first photo is taken with a manual white balance setting that renders the colors neutrally – the grey areas on the reference card have exactly the same shares of red, green and blue.
On the second image the automatic white balance of the camera has resulted in warmer colors. The rendition of the color table would not pass a test for being accurate but the warmer colors suit Freddy well.
The message is: Do not stick too much on „accurate“ color rendition, if you like warmer or cooler colors better, do not hesitate to give your images a different atmosphere with them.
But it matters that you understand white balance and are able to control the colors in the way you want to have them.
If you want to have a better comparison of the two images above: Watch the additional copy below, let your eyes rest on it for a moment and then move the mouse pointer over it to flip to the second picture.