Learn creative practices for caustics, reflecting and refracting light rays, and time-saving rendering techniques that can be used in an array of scenarios that require caustic effects. Software required: Maya 8 and up (Maya 2008 required for project files).
Learn creative practices for caustics, reflecting and refracting light rays, and time-saving rendering techniques that can be used in an array of scenarios that require caustic effects. Contains over 2 hours of project-based training. Perfect for intermediate artists. Popular highlights include: Understanding Caustic Photons; Emitting Photons from Various Light Sources; Controlling Photon Energy and Decay Rates; Altering Photon Color Attributes; Separating Caustics from Direct Lighting; Tuning Caustic Scale, Radius, and Accuracy; Photon Tracing with Transparent Surfaces; Saving and Re-using Caustic Photons Maps; Dielectric Material Properties; Troubleshooting Rendering Errors; Using the Map Visualizer; Photon Interactions with Maya Materials; Photon Interactions with mental ray Materials. Software required: Maya 8 and up (Maya 2008 required for project files).
Kyle was one of the first authors for Digital-Tutors (now a Pluralsight company) and has been a part of the team for over 10 years. Kyle began his career in computer graphics education as a college instructor and worked as a Digital-Tutors rendering tutor and curriculum manager since 2002.
Introduction and Project Overview Hello, and welcome to mental ray Workflows in Maya: Caustics, presented by Digital-Tutors, an Autodesk authorized publisher. My name is Kyle, and I'll be your instructor guiding you through the process of using caustics in mental ray to achieve a very high level of realism in your rendered environments. Now, in nature, light can interact with reflective and refractive surfaces in order to create some very remarkable effects. Now caustic patterns are among the best examples of this interaction, and this refers to the complex patterns of light that are created when light is focused by reflective or a refractive surface. Now in mental ray, these light patterns can be created with caustic photons, and mastering this feature is an essential step toward creating highly realistic renders that closely mimic the way that light interacts with objects in the real world. So we'll begin our training by exploring photons in mental ray, and the process they use to simulate these caustic light patterns. Now from there, we'll have a look at some specialized attributes that are used to control the intensity and the complexity of your caustic patterns, and we'll take a look at some features to optimize your rendering times, as well as practical lighting examples that are specifically designed to give you a stronger knowledge of caustics in mental ray. Alright, so in the real world in the field of optics, caustics basically refer to a light ray or multiple light rays that come from some kind of a direct light source, which are able to be reflected or refracted through a surface, and then in turn projected onto another surface. Now that resulting light pattern that we see is what we would call a caustic pattern or a caustic effect. Now, in mental ray, that particular type of an effect, that caustic pattern, is created with the use of photons. Now, photons are emitted from a direct light source within Maya, so in order to start to get these caustic effects, the first thing that we need to do is create some kind of a direct light source. So to do that we're going to go to Create, Light, and we can really choose any of these lights as a point of emission for these caustic photons. Now the light that we choose, however, is going to be very important. For example, if I were to choose a Point Light, just move this into my scene, if I were to use this Point Light as the basic emission source for my caustic photons, what's going to happen is these photons are going to be emitted from the light in the exact same manner as it emits direct light. So in the case of a Point Light, it's able to emit light out in a 360 degree area, so it's going to be shooting these photons out in all of these areas as well. Now, in some situations that may be a good thing, but most of the time when it comes to using caustic photons, you probably don't want to use a Point Light, and the reason is because usually in your scene there are only going to be a very few objects that are actually going to require these caustic effects. So if you were to use a Point Light and start to emit photons, what you're going to wind up with is a lot of wasted photons that aren't able to be used in the calculation. And as we'll start to see in the next couple of lessons, the process of calculating these caustic photons is a very expensive process, and when I say expensive what I mean is that the calculation of these photons can take a long time. So really what you want to try to do is optimize your use of the photons and try to concentrate those into just the areas that you need. So, what I typically like to do is, rather than using a Point Light is to use something like a Spot Light. Okay, now the Spot Light, just like it's able to create real light sources if I were to press 7 on my keyboard and take a look at the direct light here in my view port, you can see that the light from any kind of a Spot Light is very focused, it's very directional. So, as I mentioned, when it comes to the photon emission it's going to follow the exact same pattern, so what that means is if I use a Spot Light as my point of emissions for those photons, these caustic photons, I'm going to be able to concentrate them in a very small area and just use the caustic photons on the areas that I need, and so that means that I'm not going to have to worry about wasting a whole lot of unnecessary photons in these areas, and that's going to be a much, much more efficient calculation and a much faster render than if I were to use something like a Point Light or even an Area Light for that matter. Alright, so now that we know the basic processes by which these photons are going to be getting into our scene, which is going to be through these direct light sources, what we'll start to do in our next lesson is start to explore some of the attributes of these actual lights that are going to start introducing these photons into the scene itself.