Sometimes taking a neutral position on things isn’t really the safe thing to do – sometimes it’s actually downright destructive!
Auto White Balance. Your camera’s Auto White Balance, or AWB is a typical fallback lighting selection used by most of us because we assume that the camera is smarter than we are, or at least more capable of judging lighting conditions. But assuming that AWB will always diagnose lighting and set the proper color temperature is risky. Here’s why.
The first thing to understand is that in the language of RGB color, equal values of red, green, and blue (like red 128, green 128, and blue 128) produce an absolutely neutral gray color.
The AWB algorithm in your camera always assumes that there is a detectable neutral gray component present in every scene. It then examines the light reflecting from objects in the scene and locks onto the cluster of pixels whose values are closest to equal. The AWB algorithm then dutifully forces those colors to become absolutely neutral value. And at the same time, all colors in the scene are shifted to the same degree. This is the heart of auto white balance.
This is all well and good IF that color in the scene is suppose to be neutral (gray) in color. This color shift will then actually improve the balance of color in the image
But, if the scene doesn’t actually contain a neutral gray component; if there is a bluish –somewhat-gray item (like the snow scene above), and you capture the image with Auto White Balance, there will be trouble. The image on the left was captured with Daylight setting. The image on the right was captured with AWB. Notice that the camera interpreted the bluish snow as “neutral,” rendering it unnaturally gray. The image processor in the camera changed that bluish color to neutral gray, and shifted all the other colors in the scene in the same direction on the color wheel absolutely destroying the emotion of the scene.
Gray is not a color. Color balance is all about gray. Neutral gray is the colorless backbone of accurate color because it contains equal values of all three RGB colors. Gray is the gold standard by which all accurate color is judged. Auto White Balance is useless unless there is an element of this absolutely neutral “color” in the scene.
With all the whiz-bang technology and automated functions in today’s cameras, we photographers (whether accomplished or improving) are tempted to become a bit lazy. Successful photographers (like the ones who inspired you to purchase your camera) didn’t get successful by accident. They invested time and hard-earned money in their own understanding of the art. But it didn’t stop with the art/composition element. Their understanding of photography included learning about the way light behaves.
The best color balance setting is the one you will choose after evaluating the lighting. And that all starts with understanding how color behaves. When you get beyond learning composition and and the mechanics of your camera’s controls, you realize that learning about light is THE most important part of photography. You soon learn that light is the one thing you MUST learn to control.
If you really want to understand what makes color work, you need to understand how light behaves. And here’s where I can help you. I’ve created a very entertaining and easy-to-understand video series that will teach you these fundamentals and get you on track to capture and produce amazing color. 
