The subject of white balance not only causes confusion for newer photographers, but for many who have had a camera in their hands for years as well. At the Aperture Academy, we hear it all when it comes to white balance.
"I just leave it in auto."
"I can use everything else in manual BUT that...."
"I've been meaning to ask someone about that...."
"I have no idea what it is...."
It's a crazy part of our cameras that most people ignore, or will often just figure they'll adjust it when they get into Photoshop.
"You can just adjust that in Photoshop, right? I don't NEED to mess with it in the field, do I?"
The simple answer is, no. The more detailed answer is, if you shoot in RAW, you have an opportunity to adjust your white balance at home, on the computer...BUT you're missing out on a valuable tool, and let's face it, by choosing computer adjustments over in camera, you won't understand what white balance actually is.
Let's take some of the mystery out of the subject, shall we?
To put it plainly, white balance is your camera trying to figure out where white is in your scene so it can properly adjust the rest of the colors and make your photograph look normal.
The problem is, white behaves differently in different lighting situations. To help remedy this problem, the camera uses the Kelvin scale. This scale runs from about 2500 to 10,000 degrees. (Different cameras have different ranges, but most land somewhere in this range.)
At different times of day and in different light, white is located at a different temperature on this scale. This is why sometimes when you take a photo it looks yellow or blue, even though that's not how the scene presented itself to you.
It's important to know that every color of light has a different wavelength, and this coordinates with a different temperature, which your camera sensor is able to pick up. Warmer tones are in one range, and cooler tones are in another. Once the camera has established where white is, then it can place these other values on the chart. The lower the number is on the Kelvin scale, the cooler the tones, and vice versa.
[To learn more about the Kelvin scale, see photo examples, and get more information on how easy it is to use the white balance settings on your camera, continue reading the full article here.]