The paint swatches, above, illustrate the effect light from an incandescent light, such as the type used in an ordinary household lamp, has on color. Because of its yellow/orange tinge, it actually enhances the warmer colors, when compared to the same colors lit by ordinary daylight. but it radically alters the cooler colors.
When we shoot resource photos and the camera is set on auto, the white balnce function corrects these radical color shifts. However when we actually paint under the same lights, all our color choices are affected.
It could be argued that this is no big deal, since most paintings are viewed under a warm light at home or in an art gallery, But if the goal is to paint what we see, then we have to at least be aware of the role white balnce plays in our color choices.
For the true plein aire painter, a painting with subtle warm tones, when viewed inside, will lose much of its color nuance, because warm tones blend together under incandescent light. If the painting also contains vibrant cool colors, such as the cerulean blue swatch, above, it will lose much of its brightness.
If a student is painting a still life lit by an incandescent light while the canvas is lit by either daylight corrected or regular fluorescent bulbs, then the white balance problem is further exascerbated, especially when you consider that the Old Masters painted still life setups lit by daylight through a window, which was the same light that lit their canvases.
replicates window light.
