Caustics are really great light effects that you can observe in liquids, glass objects and gems. We are able to simulate this effect with 3D Studio Max perfectly.
This tutorial about Caustics that I wrote for my students of the Florence Design Academy (
href="http://www.florencedesignacademy.com">www.florencedesignacademy.com) will work only if you enable Mental Ray (this tutorial was made in Max 8).
Let's Create a small room like in the image below ( try to do that in realistic sizes, it is important that you make the setup of the unit system, only in this way Mental Ray will give you an optimal end result since it will consider all measurements of the objects in the scene for the final rendering).
There are several techniques to create a correct illumination. In the case of the room I have created 3 long free area lights as you can see in the image below ( you can find them under photometric lights).