[flow_default] Transcription: 02 - What is Ambient Occlusion.json

transcriptions/02 - What is Ambient Occlusion.json

@@ -0,0 +1,7 @@
+{
+  "audio_file": "02 - What is Ambient Occlusion.wav",
+  "text": "Welcome to this bonus lesson all about ambient occlusion. Now if you've been paying attention in the lessons that I've been doing and hopefully you have been, you will have noticed that in some of the exercise videos I've actually kind of introduced this ambient occlusion very very briefly in the form of like hey go to your render settings turn this trust me, it just makes your render look more better. Okay? And that's basically all I had said about that up until this point. So what I actually want to do in this video is kind of go more in depth into what AMI inclusion or AO is all about and what's going on behind the scenes and why it makes your render look more better. So in my scene right now, I just have this nicely lit with some side lights and then just a little background fill light that's back behind my character facing the Psyche. Okay. And we have some pretty nice lighting and shading going on. Let's go ahead and see what happens if I go to my render settings here and apply this ambient occlusion render effect. Okay? So I'm just gonna turn this on and let's just kind of watch and see what happens. So you're seeing that in the nooks and crannies of the little marshmallow man here, it's getting darker. So what's actually happening behind the scenes in ambient occlusion? What does the ambient occlusion actually mean? Well, ambient occlusion actually mean? you can see that kind of darken things up and this kind of really accentuates the details. It adds some really nice contrast to our scene. And you can see with AMI inclusion off, we actually lose the shading that's occurring in the mouth area. And because the shadows in my lights aren't that dense, they're a little bit more subtle. It almost looks like, because the shadows are that light and that subtle looks like my my marshmallow guy here is just kind of floating he doesn't look grounded he doesn't look like he's actually has his feet planted on the ground but with that ambient occlusion we get that really nice shading wait for it it's gonna happen this really nice shading you can really tell now that that foot is on that ground or that that background psych object I have in my scene here. So let's just kind of go over some of the settings here. And the first one up is this color and it's adjusted by this gradient. And basically what this gradient does is if I move this all the way to the right, you're going to see a lot more of this dark black color on the gradient be appearing in our ambient inclusion. Okay. So we can actually adjust this, the darkness there, moving color chips. We can also change the color of our color chips as well. So like I said in the previous video, in the previous lesson, about lights, about how in real life, no shadow is completely 100% black. There's always some kind of hue in there and same thing with light color. The sunlight has a little bit of yellow. a that very very nooks and crannies of this object where two objects are immediately touching you can see a lot more of that blue where that light is occluded more but then like this hat here we have very little of that blue color so it's more exposed to that ambient light source that is driving the ambient occlusion so you're seeing a little bit more of the middle values of that gradient happening so this is kind of a good way or a good experiment to kind of see how these colors are being applied and how the ambient inclusion is kind of being spread out across our objects. So I think I might actually leave these colors like this just for demonstration purposes. One thing that I typically don't ever touch is this furthest right color chip right here. And that's because if I go ahead and maybe change this to yellow, you're gonna see this basically tints our entire render. So very rarely will you ever need to kind of change this for this right color chip from anything but white, unless you want that kind of color wash, which I'm not sure why you'd really want to, but you know, hey, knock yourself out, right? So next on the list here is the maximum and minimum ray length. Now what does that mean? Well, if you see I adjust, if I just adjust the minimum ray length here to 35, let's see what actually happens in our render. And actually see that the density of the blue and actually some of the orange is becoming more and more dense. And what's actually happening is we're adjusting almost like we're adjusting the gradient here where the darkest value is kind of pushed out 35 centimeters, so it doesn't actually start to fade until that amine inclusion is like 35 centimeters away and then it starts to fade away So we're kind of adjusting the threshold here So if I maybe bring this maximum ray length down to 35 we can see exactly what will happen now where we're kind of compressing it even more. It's not as spread out. So basically what the maximum and minimum ray length does is define how widespread or how dispersed or how wide our ambient occlusion shading goes. You can see that as we brought this maximum ray length down, you can see a lot less of the colors of any, I mean, occlusion shading are being applied to our object because we're basically, we haven't blurted out as much as it is if we really crank this up to say 200. Now, one thing to keep in mind with, now you can really see our shading going very wide and you're seeing a lot more orange than you did before. One thing that to keep in mind with this maximum ray length is the higher the number, the longer the render time. So it's always good to kind of take stock of the size of your scene. So for example, we have a maximum ray length of 200. You can see that our orange kind of spreads out a little bit and then you really can't see that shading anymore. If I bring in a cube and let's just kind of move this out of the way. You can see that a cube by default is 200 by 200 by 200. So you can see that my actual character is way smaller than that, not way smaller, but it's smaller than 200 centimeters. So what we're actually doing is kind of going overkill with that 200 centimeters just because that's such a wide swath. We're kind of needlessly having our ambient inclusion search that wide to create that shading. So this is an example, if I just delete that cube again, I was just kind of to get a sense of scale of our scene. Really, this is overkill. So let's actually bring this down to 100, and this was what we had it before. You can see that, okay, our shading is still pretty good. Let's actually bring this down to, say, 50. And again, that render time was about five seconds. Actually, this render time's about five seconds as well, but you can see that our shading is spreading out less. If I bring this down to 20, you can see even less of the orange and less of our AMA inclusion shading occurring in our scene. And if I bring it down to say five, you can see even less. Okay, so hopefully you get a good idea of what the minimum and maximum ray length is. It adjusts how far from an object the ambient occlusion travels and kind of disperses. Now, we also have this dispersion and basically this is just a basic blurring of the of the ammucleusion shadowing if I bring this to zero you're gonna see that we're gonna have no blurring at all it's just kind of almost like a psychedelic effect we're really not getting any dispersion at all we're just getting kind of clustered and really compact and high density areas of the am inclusion. So very, very typically I will not touch this dispersion at all. I'll always leave it at 100% because if I want this to be a little bit more contrasty, I can always adjust the minimum and maximum ray length and get a similar effect. But typically I don't really touch that. I typically like soft the ambient occlusion, but if you like a little bit more harsh ambient occlusion shading, knock yourself out with this dispersion and kind of fine tune how you want this. So a little bit more stylized, a little bit less realistic to adjust that. So let's just kind of reset some of our settings here. Next up are our accuracy and minimum and maximum samples. Now this basically controls if I zoom in up and style than a super super perfect render. Another thing to keep in mind with these accuracy and minimum maximum set sample settings is that the increase render time of course. So you'll kind of want to figure out how much grain do you what can you live with basically. So if I crank this up to 100% accuracy let's kind of let this go and you can see we're kind of we're really not getting rid of that much grain because a lot of these settings the your entire render because that's a waste of render time. There's some areas like the darkest of dark areas where it's okay to have grain because it's so dark it's not noticeable or where the shadow is so dispersed that you're not going to notice grain there either. So what this tries to do is optimize the render time and Cinema 4D's renderer tries to judge which areas like we don't need to waste sample renderender time on this area, but this area the noise will be more noticeable So spend more render time there and this is basically the minimum samples is like for the for the areas that won't have a lot of grain at all anyway So you typically don't want to touch that or make this number too high But where you do want to crank up the samples is right here the maximum samples So if I kind of crank that up and let's kind of see here, it's going to be very fine. But this is really smoothing out and I can barely notice any kind of grain at all. Let me actually maybe move the darker values out here so we get more of a sense of the grain. And I think most of the grain here is gone. Again, we're increasing the render time. So we're seeing a little bit of grain. So maybe we crank this up to 500. It's always a push and pull with these render settings because every scene is different. The scene that you might render will be different from this one and the scale will be different as well. So if you have a large scene with large objects, number one, you're probably gonna wanna crank up this maximum railing so the shading kind of reaches the further away objects. So what I like to do is kind of just play around with these values here, especially the accuracy and see how low can you go, you know, like at a party where you're doing the little thing and I forget the name, what that is, where you go under the pole, whatever that is. It's always about how low can you go before you start to notice the samples and how well can you go before you fall on your butt. So always kind of crank high and see what the highest level is. It's like, okay, that definitely, there's no grain there. And then just kind of go back and see like, okay, can I get away with 300 samples and see like, okay, well that still looks pretty grain free. I think we can pull this back even more. Maybe go to 200, not 1200. Goodness gracious. And then just kind of keep stepping back. And especially if you're going to be far away, like if your camera's going to be far away, you're not going to even notice, you're going to notice grain even less. So you can probably make this even lower. Let's go to contrast next. Contrast is like the dispersion where it adds contrast. Contrast crunches the levels and does not adjust the dispersion level at all. You can see that we're doing a curves adjustment and crunching those levels. You're going to see a lot more of those darker values and a lot of this dark dark ambient occlusion shading happening here. One thing I like to do, so you can crank this all the way up to 100 and you can really get this cranked up, you're seeing a lot more of the darker shades of the ambient occlusion. So just think of that as like super super dark black areas would be occurring on here. Again, you can see a lot more of the grain now as well with the contrast. contrast in the negative direction as well. One other important setting is if you're using transparent objects with transparent materials like glass, you want to make sure you check this on. Self-shadowing only is that this object will only kind of self-shade itself. It won't actually shade any objects around it. So you can see that it's no longer, our marshmallow man is no longer affecting the other object. And neither is the floor of the background psych affecting the marshmallow man. So everything's kind of antisocial and keeps it themselves. That's kind of self-shadowing. Invert direction is a really, really cool effect. Let me just bring the contrast to zero and kind of see what's going on. Maybe bring this lower, the maximum ray length. And let's do invert direction. And basically, what you'll see this does is inverts all of the shading and gets this kind of wacky effect. And if I just kind of maybe adjust the shades here so we don't get the colors anymore, maybe adjust this to a lighter gray here. Basically, you can see that we just totally reverse the dark and light areas of our object. And basically what this is good for is for maybe if I make this maybe yellow or something like that. What this tries to do is it's a good emulation of what's called subsurface scattering, which is another fancy pants word and kind of another render technique or a material technique to Get the effect of like if you had And let me just do this really quick I have my cell phone light and if you put your cell phone light right on your finger It's the light that's kind of dispersing through a semi-transparent surface So like the light traveling through my finger that subsurface scattering right there. So this is basically an effect that is very similar to that, that tries to recreate that kind of effect where lights kind of passing through, maybe get like a jade or something you can see through kind of effect very easily without actually having to do the subsurface scattering effect. So that's there as well. Sometimes it looks like maybe an object has a kind of an inner glow if you adjust the type of colors that are in here as well. But that option is there if you want to play around with it. Just kind of inverts it. Kind of cool effects. I'm just going to turn that off. But hopefully you understand what ambient inclusion is now. How it affects your render. How you can try to manipulate things, but again, always keep in mind the render times and just kind of keep it, making sure you don't kind of push it too much. With great render power comes great responsibility like the old wise men Uncle Ben once said. So knock yourself out with aiming inclusion, just watch them samples, but have fun, alright?",
+  "language": "en",
+  "confidence": null,
+  "duration": 1240.32
+}