Why Composited People Look Pasted: Lighting and Color Coherence

You can nail every facial feature and still produce a composite that looks obviously fake. I've watched people burn weeks on identity preservation, get it perfect, then ship an image where two people supposedly standing in the same room are lit by two different suns. The brain catches it instantly, without being able to say why. Lighting coherence is the part nobody writes about, so here's what I've learned making it work. Why "pasted" is a lighting judgment, not a geometry judgment Human…