Lighting tells: shadows and light sources that disagree
Every shadow in a real photo points away from a real light. Check that they agree.
Physics forces a photo to be consistent: one sun means shadows fall the same way. Image models blend many lighting setups they have seen and sometimes put two suns in one scene.
Generated images also love a certain kind of light: soft, golden, glowing from everywhere at once. Faces are evenly lit without a harsh side, and the background has a gentle haze. It looks like a good photographer took it, which is exactly the problem when the setting is a random kitchen.
Real photos taken by ordinary people are often badly lit. Blown-out windows, harsh flash, mixed colour temperatures and deep shadows are signs of a camera that could not cope, and AI rarely makes those mistakes on purpose.
Checklist
- Find two or more shadows and check that they point the same direction.
- Ask where the light comes from. Can you see or infer the source?
- Notice light that is too perfect for the situation, like studio glow in a garage.
- Look for blown highlights and noisy shadows, which point to a real sensor.
False alarms
Multiple lamps, reflectors and flash create real scenes with several shadow directions.
Test yourself
Put it into practice in the daily AI or Real game or the endless quiz.