LuxCore – Open Source, Physically Based Renderer for Blender

luxcorerender.org/

https://en.wikipedia.org/wiki/LuxCoreRender#:~:text=Although%20the%20original%20LuxRender%20is,rendering%20caustics%20in%20some%20circumstances.

Note: Although the original LuxRender is a full spectral renderer, the new LuxCoreRender drops full spectral rendering in favor of simulating spectral dispersion when required.^[14][15] However, this leads to some inaccuracies when rendering caustics in some circumstances.^[16]