This tutorial is from a technique that I used many years ago. I’m sure some of you will remember this as I used to have a written tutorial on the Hypa website many moons ago! The results from this are quite unique and you can create some really beautiful effects by rendering a few passes and comping them together.
The idea is that we take a 3D model of a logo or perhaps some type, add a refractive material to the object and then shine a caustic casting light through the object.
By hiding the object from the camera we can project caustics onto the surface behind our logo. All you need to do then is add some animation to your objects and lights, then fine tune your settings.
I must warn you that it can be very processor intensive when you start blasting millions of photons through complex surfaces. The render times are actually really fast, but the calculations required before each frame is rendered can become very long if you’re using several lights with a few million photons cast from each. The trick is to find the right balance between render times and quality. In the example I show at the end of the tutorial, I used two million photons for each light and there were four lights in the scene. It rendered in a few hours which is very acceptable. However I did try rendering with 10 million photons on each light and I think it basically maxed out the RAM on my machines as the render time was looking like it would be 2 or 3 days. Ouch!
Here’s the tutorial, don’t melt those processors all at once… Have fun!
Cinema 4D Tutorial – Refractive Animation with Caustics