Just a simple example of how the concept of Color Temperature can be used to give more life and believability to an image. Color, value and hue all work together in nature and cannot be separated. When you paint try not to just have light yellow and dark yellow (which can look muddy like in the top example), but consider that saturation can increase and the hue can shift when the light decreases in strength. Think of light as energy instead of just a value or black and white. If you turn on a light bulb slowly the filament will start by glowing a deep saturated red, then as more energy is added (higher temperature) the color will shift towards orange, then yellow and eventually to white.
For more information on this idea I talk about it in my DVD with the Gnomon Workshop ( [link]
). But I found this example I had created awhile back and figured it would be good to share.