Now that we know a bit more about our lighting, we can use that to figure out how white balance works (remember, equal parts of red, green and blue makes pure white):

If we tell the camera that the light on the subject is disproportionately composed of red wavelengths (tungsten), it will lower the amount of red and increase the amount of blue and green in the image to balance the overly red light out to keep our whites white.

If we tell the camera that the light on the subject is neutral (daylight at noon on a clear day), it will make only very minor adjustments to the colors in the image to keep white objects white.

If we tell the camera that the light on the subject is disproportionately composed of blue wavelengths (shade), it will lower the amount of blue and increase the amount of green and red in the image to balance the overly blue light out to keep white looking white.

In short, white balance is used to offset the colorful side effects of the lighting on our subject. We approximate the type of lighting through a color temperature which closely approximates the types of lighting we commonly run into.

Now that we know a bit more about our lighting, we can use that to figure out how white balance works (remember, equal parts of red, green and blue makes pure white):

If we tell the camera that the light on the subject is disproportionately composed of red wavelengths (tungsten), it will lower the amount of red and increase the amount of blue and green in the image to balance the overly red light out to keep our whites white.

If we tell the camera that the light on the subject is neutral (daylight at noon on a clear day), it will make only very minor adjustments to the colors in the image to keep white objects white.

If we tell the camera that the light on the subject is disproportionately composed of blue wavelengths (shade), it will lower the amount of blue and increase the amount of green and red in the image to balance the overly blue light out to keep white looking white.

In short, white balance is used to offset the colorful side effects of the lighting on our subject. We approximate the type of lighting through a color temperature which closely approximates the types of lighting we commonly run into.