Color temperature is a characteristic of light that describes the warmth or coolness of the light source. In simple terms… you will hear people refer to an image of warm (too orange) or cool (too blue). We want our skin tones to be realistic and true to life. Because different types of lighting have different color temperatures, we have to set our cameras to appropriately capture that skin tone. When we leave it to the camera (auto white balance) to make this decision for us, many times it will miss… for this reason we use a white balance tool (expo disc or white balance target) to determine the exact color temperature, then we set the camera to this color tone.
Most of the time we will photograph using a custom white balance. Setting the custom white balance on your camera is easy: See the following link: Custom White Balance