Color Temperatureand White Balance
Light, whether it be sunlight, moonlight, flo-
rescent light, or light from a Speedlight, is
measured using the Kelvin scale. This meas-
urement is also known as color tempera-
ture. One of the advantages of using a
digital camera is the ability to measure the
color temperature of light through the lens.
If your Nikon digital camera is set to an
automatic light balance, then it automati-
cally adjusts the white balance for the shot
you are taking. The result of using a correct
white balance setting with your digital cam-
era is correct color in your photographs.

What is Kelvin?

Kelvin is a temperature scale, normally used
in the fields of physics and astronomy,
where absolute zero (0º K) denotes the
absence of all heat energy.
Kelvin and color temperature is a tricky con-
cept as it is opposite of what we generally
think of as “warm” and “cool” colors. On the
Kelvin scale, red is the lowest temperature
increasing through orange, yellow, white,
and shades of blue are the highest temper-
atures. Humans tend to perceive reds,
oranges, and yellows as warmer and white
and bluish colors to be cold. However, phys-
ically speaking the opposite is true as
defined by the Kelvin scale.
To make this even more confusing, when you
set the white balance on your camera using
the Kelvin scale, the higher the temperature
you select, the redder the image is. What you
need to remember is that when you are set-
ting the white balance on your camera, what
the camera is actually doing is filtering out
the color of the light that matches the color
of the temperature in Kelvin scale.

Preset white balance

Most digital cameras, especially digital SLRs,
let you choose the white balance setting
manually and even set custom white bal-
ance settings. However, for the most part,
automatic white balance settings work well
in most situations. The next series of images
shows the difference in white balance set-
tings from a photo shot with multiple Nikon
SB-800s. Each photo represents a different
white balance setting, with color tempera-
tures ranging from 2800K to 7500K. The
lower the color temperature, the more blue
appears in the image. The higher the color
temperature, the more red and yellow
appear in the image.
Don’t always rely on the auto-
matic white balance settings,
especially in mixed light or
other difficult lighting situations.
Tip
62 Part II ✦Creating Great Photos with the Creative Lighting System
09_045275 ch03.qxp 11/28/06 8:24 PM Page 62