Painting light is the skill that separates competent digital artists from compelling ones. I've watched my own work transform over the past eighteen months specifically because of how I changed my approach to light and shadow.

The old approach: pick a shadow color that's darker than the light color. Add it to the shadow areas. Done. This produces flat, unconvincing results because it ignores how light actually behaves.

The new approach: shadow is not dark light. Shadow is the absence of the direct light source and the presence of ambient, reflected, and indirect light. On a clear day, shadows are filled with blue skylight. Near a warm surface, shadows pick up reflected warmth. The transition between light and shadow — the terminator — has its own subtle color shift.

I started noticing this in photographs and then in real life constantly. Once you can observe light accurately, painting it becomes a translation exercise instead of an invention exercise. The paintings started looking real when I stopped imagining light and started observing it.