Quote - photons and pathtracing are what makes caustics work?

Photon mapping, etc. can be used to map physically accurate caustic effects, yes. It's important to use correct refractive surfaces for this too (like glass material).  However, not all caustic effects in CG are done this way.  It's a complex subeject when you really want to understand the physics of it all, but there's dozens of ways to "fake" caustics, and there's different kinds of caustic effects too.  Reflective caustics, refractive caustics, etc.  They add to photorealism, but faking them is usually more than good enough to trick even the most experienced observer into thinking you did them the physically correct way.

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Tools :  3dsmax 2015, Daz Studio 4.6, PoserPro 2012, Blender v2.74

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