Here's a quick 10-minute tutorial on how to create good looking caustics using V-Ray without spending hours in calculations. The whole concept is pretty simple and the final setup should not take long nor stand on one's way while working on a scene.

First, we have to understand why the heck caustics take so long to calculate (if you want something that looks remotely good). And there's only one word to explain it: waste. What most people do is to try to generate caustics using the same lights that light the scene, and that causes a huge waste oftime. Simply because you don't need V-Ray to calculate every single photon a light emits. You only need those that actually cause the caustic effect (which are the minority, of course).

Then, what if you could calculate just those photons? What if you could simply forget about all the waste and complicate settings and use your system's resources to calculate only those few to maximum effect? That's the objective of this tutorial.


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