Subtitles of the Movie

So, now this Render has completed and it looks much better than just the standard global illumination rendering. Now what we're doing is we're seeing some extra highlights on the back of these spheres as the light bounces off this sphere and then reflects into that one. Very nice look. It just looks that much more believable and realistic if that's the goal of your render is realism. The issue with this is that this Render took, on my system, about 10 times longer than the other system. I cut that part out so you didn't have to see that, however, that's the penalty you pay when you start working with Indirect Lighting, is significantly increased render times. For a single image, not so bad. If you're doing an animation that may have thousands of images in it, that can be a real problem over time. It can actually extend your rendering from days to weeks for multiple renders, and that's where Ambient Occlusion comes in. Ambient Occlusion means the light that is around the area is being blocked Ð occlusion Ð the word occlusion means to block or obscure. If you look at your desk around you right now, you'll notice that the objects sitting on it, the closer you get to the object, whatever they're sitting on, it's a little bit darker, and that's because the object itself is interrupting the light from hitting that spot. It's occluding it, it's blocking it. Well, what Ambient Occlusion does in Carrara is it just says that within a certain distance I'm just going to make it that much darker. I'm going to fake shadows with occlusion. Well, that's the cool part, and it saves significant amount of time in your render. It doesn't look quite as realistic, but let's take a look at it and explain a couple of the things we're dealing with. The Ambient Occlusion option is over in the right-hand of the Panel, just below the Full and Direct Lighting. When you turn on Ambient Occlusion, Full Indirect Lighting turns off, and it starts to do a little bit of guesswork on that in terms of what it does. The payoff is a big bump in render time. It saves so much time. Let me go ahead and render that out so you can see the difference in look now. The one thing I will tell you is that Ambient Occlusion pays very careful attention to your scene size. This is a medium sized scene at 30 foot by 30 foot, that's about how large the plane is that this is sitting on. The Ambient Occlusion radius is 08 feet. That's so small for this scale scene and it's going to be almost invisible, so this is something I actually want to increase to something more like .5 feet, and this is going to give me a more believable type of interaction for the size of my scene here. Of course, if we're dealing with skyscrapers and buildings, you'll just have to finesse that and work with it in your scene. But now let's take a look and see what this looks like. We can see right now as this is rendering that I'm actually showing you the rendering it's going so fast. The speed penalty for using Ambient Occlusion Ð you pay a little bit more for it in render time, but nothing like Indirect Lighting. At this point in time in the Indirect Lighting we had only gone through the first two render tiles, not even quite that, and this one will be done in that amount of time. By the way, the render time I'm showing on your screen are representative of how many processors you have in your computer. Carrara is multi-processor aware. So, let's take a look at the differences of what's going on here right now. The render's turning out to be a little bit darker than the Indirect Lighting and we can see the manifestation of Ambient Occlusion. Right where my cursor is, the little hand, you can see that as the cube gets next to the sphere suddenly it's getting darker. That is the fake shadowing, the Ambient Occlusion that's taking place. Wherever we get a juncture of two objects coming together we're going to get some darkening. This can be used to a tremendous special effect if you want to that has nothing to do with reality, but it's a way to kind of cheat reality a little bit and simply give a more realistic look without having to wait minutes or hours for render time to take place. There are some other features that I'm going to confine to the Render Room Setting of how to speed up renders that do use Ambient Occlusion or Indirect Lighting, and those are subject matters more appropriate to the Render Room. So, this is the last movie of dealing with Lighting in Carrara. Some powerful tools to create some very cool effects in your scene. In our next Section we'll start working with Modifiers and Behaviors.