Watercolor technique – Painting light and shadows with color to accurately depict objects affected by light requires careful observation. It is important to notice the temperature of the light and how it changes the colors of objects illuminated by it. The temperature of natural light is warm at sunrise and sunset, and cool during midday. Also, artificial light is warm under incandescent lighting, and cool under fluorescent (or white) lighting.
Natural Light – Time of Day
Nita Leland, author of “Exploring Color” (affiliate link) describes the effect of light at the time of day as follows:
“Every time of day has its own special light. Early morning light is luminous and clear with high-key color and gentle contrasts. Tints of scarlet, blue-green and violet express the awakening day. At midday a harsher light reveals intense contrasts of color and value, bleaching out highlights. Late afternoon light has a softer golden glow, with distant objects veiled with mist moving toward chromatic neutral tones. Twilight and early evening light are luminous, tending toward blue and violet, with the sunset a deep rich crimson. Atmospheric buildup throughout the day causes red rays to scatter widely and fill the sky and landscape with color.”~ Nita Leland
Use the glazing technique with transparent and semi-transparent watercolors. For a warm, luminous glow, paint a very light yellow as the first layer. Use analogous colors in multiple layers for a bright, clear glaze. Use Primary colors to create Secondary colors. To tone down the intensity of a color, use its complementary color layered over or under it.
Natural Light – Color In Shadows
In nature, shadows are not a flat gray or dark neutral color. Instead, the local color of objects are visible through the shadowed areas. Look closely and observe that there are more than one color within the shadows. For warm shadows use analogous colors that are darker than the object’s local color. Use the wet-on-wet technique and drop in colors in the shadow area and let them mingle naturally to create more interesting shadows. For cool shadows use transparent blues, violets, and greens.