A 3D portrait lighting simulator
Lumen Tool is a free 3D portrait lighting simulator that runs entirely in your browser. Most alternatives are either expensive desktop software or outdated browser tools that cycle through pre-rendered photos. Lumen renders shadows in real time using Three.js, loads in under a second, and requires no install or account. It's a single HTML file under 1MB. Move a light, watch the shadows shift live. That's it.