Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member
For objects rendered in a 3D application to take on a genuine level of believability in the viewer's mind, they need to interact correctly with the environments around them. Adding real-world lighting effects such as caustics can oftentimes make all the difference in the world when it comes to creating a believable shot. That's why in this video we are going to look at using photon mapping to generate caustic effects in our Maya and V-Ray scenes. Now first of all, we want to make certain that we have viewing our scene through the correct camera, we have a Caustics Camera already set up, so if we just go and choose that from our menu system.
And of course if we just make certain that we select our camera, in case we want to do any work with it. In this particular instance that is highly unlikely as the Caustic effects are, well they really are lighting and not an in-camera effect. We now need a caustic generating material of course if we come up to the Window menu, if we come to the Rendering Editors and pull up the Hypershade window for ourselves, you can see if we just scroll down in here that we have a Glass Material already set up. Now we could use a highly reflective material such as a highly reflective metal that would give us reflective caustics in our scene.
As we have a Glass Material here, we are going to work with refractive caustics. The steps for generating them the system controlling them is exactly the same. So whichever one of those particularly options you want to work with that is absolutely fine. Of course with our material, we are going to need some objects in the scene to apply too. So let's just go and grab a couple of these pool balls, just these front two will do very nicely for us and let's right click and assign the material to the selection. So now we have our caustic generating material set up.
Now we need a photon generating light, the photons are going to be used to create our caustic effect. So if we come up to the Window menu and open up the Outliner for ourselves, just make certain that you are filtering by Lights and Light Sets, that means that only the Light types will show up in here. Now if we just like our lights, you can see we have a V-Ray Dome Light that is just applying some fill light, general fill light into the scene. We have our V-Ray OverHead Light which is a V-Ray rectangular light type. This is providing our overhead direct light source.
And we also have another V-Ray rectangular light that is designed to generate caustic photons in the scene for us. Of course it's not enabled at this moment in time, so we need to go and enable that particular option. We just want to show you how we've set it up, so that it is not adding anything to the illumination in the scene. If we come down, you can see first of all we have disabled Shadows, so there are no Shadow effects taking place. We also in its options have disabled its ability to Affect Diffuse materials in the scene, we've turned off Affect Specular and we have turned off Affect Reflections, essentially this is contributing nothing to the general lighting and shadowing setup.
There is however one option we do need to enable in here. As our two V-Ray rectangular lights are currently occupying the same point in 3D space, there is a chance that we will get some strange artifacting if we render with them both enabled. To make certain that that doesn't happen if we just with our Caustic Photon light select it, if we just make certain that that Invisible option is checked, that will very nicely take care of any potential problems for us. So we have our material set up, we've enabled our photon generating light.
We do now need to go and turn on our Caustic system. So let's come up to the Render Settings window for ourselves, we need to come into the Indirect Illumination tab. In here we have our GI and Caustic systems. Very handily V-Ray separates these two systems, so we can work with their controls independently, even though they are both lighting effects. So let's open up our Caustics rollout and if we just put a check in the On box, all of the Caustic systems are now enabled. Now we can take a render and see if we are getting Caustic effects in our scene.
And as you can see we are definitely getting some focused light Caustic effects in here. The problem is, at this moment in time they are looking quite smooth and uninteresting, oftentimes people expect quite intricate patterning in their Caustic effects and we are not really seeing that here. Well, there are a couple of parameters that we need to work with in this system in order to create that particular effect for ourselves. One of them is found in our Render Settings dialog controls, our Render Settings window controls and that is this Max photons value.
Basically, this is the number of photons that will be used to smooth or average together in order to create this particular Caustic effect, so we are now taking 30 photons and basically blurring them together inside of this effect. Of course, as we've highlighted a number of times throughout this course, any kind of blurring or averaging effect will result in a loss of detail and that is what is happening inside of our photon effect here. So first of all, let's set this value down to around about 15. Another control we want to work with is found in our lights parameters, our photon generating light.
If we come in its controls down to this Photon emission rollout, you can see there are a number of caustic options that we can work with well too, specifically. The one we are interested in is this Caustic subdivs value; this controls how intricate the paths that our photons will trace can be. So we are going to set this up to something like a value of 4500. Of course now we want to take a render, but if we just save the image that we currently have, we can compare how those two parameters will affect the Caustic effect in the scene.
And now if we just compare our two renders, you can see we've gone from fairly smooth and uninteresting Caustic effects, even though they are working, to something that just looks visually a little more interesting. You can see we have much more patterning inside of the Caustic effect itself, as we're not getting so much smoothing or averaging between photons. And we've just got some more interesting light paths being traced. You can see the photons are scattering in some interesting ways in the scene. Although, if we wanted to really brighten this Caustic effect, well there are a couple of ways that we could do that; we could first of all work with our Photon generating light's intensity value.
That multiplier will give more energy to the photons that are emitted from that light, so that's one way of doing it. We could work with this Caustics multiplier value. This would increase the Caustic effect on a per-light basis. So if we had a number of photon generating lights in the scene, we could create different Caustic multiplier values for each of them. As we are only working with the single light however, we can just work with the global control that is available inside of the Caustics rollout. I am going to just set this to a Multiplier value of 10 and we will be able to see just how much that boosts the Caustic effect in the scene.
Again, we just want to save what we have and take another render. And you can pretty plainly see how that Multiplier increased has changed the amount of energy coming from our Caustic effect. You can see we are getting much brighter refractive caustics, you can even see that the photon energy is so strong that we're getting lots of reflective caustics, a lot of bouncing between these highly reflective objects and we are even getting Caustic lighting effects over on the far side of the pool table. So you can see with just a quick tweak of our Multiplier values, we can really push the amount of energy coming from over Caustic effects.
So, as with many effects in V-Ray, creating caustics is a reasonably simple process. Once we know the steps that we need to go through in order to create it, once we know where the controls are found, we can really create some very, very interesting lighting effects indeed. What we are going to do now is move onto creating some different kinds of effects using V-Ray tools. In this instance, we are going to look at creating fur using the V-RayFur tool.
Get unlimited access to all courses for just $25/month.Become a member
Access exercise files from a button right under the course name.
Search within course videos and transcripts, and jump right to the results.
Remove icons showing you already watched videos if you want to start over.
Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.
Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.