Tutorial: Create Chromatic Aberration in Nuke and After Effects

Create realistic chromatic aberration with this After Effects and Nuke tutorial.

Ready to make your 3D render look less perfect and more real? In this lesson you'll learn how to use chromatic aberration to do just that. It's a bit of a mouthful, but its an easy effect to understand. Joey is going to show you how to do this in both Nuke and After Effects. If you've been wondering what the differences between those two programs are, there's no time like the present! Take a peek in the resources tab if you want to grab a 15-Day free trial of Nuke to play around with.

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Tutorial Full Transcript Below 👇:

Music (00:00):

[intro]

Joey Korenman (00:22):

Hey there, Joey, here for school of motion in this lesson, we are going to take a look at chromatic aberration in both after effects and nuke. Now what the heck is chromatic aberration and why do I need to know about it? Well, chromatic aberration is one of those things that happens sometimes when you shoot photography, it's a real world artifact of the imperfectness of the lenses that we use on our cameras. And so adding it to CG renders can make them feel more photographed, which adds to the realism and also looks really cool. I'm going to show you some ways to achieve the effect without any third-party plugins. Don't forget to sign up for a free student account. So you can grab the project files from this lesson, as well as assets from any other lesson on the site. Now let's hop in and get started.

Joey Korenman (01:07):

So what I want to show you guys today is how to achieve an effect called chromatic aberration. Um, and it's kind of a very technical name. Um, but what it means is that, um, sometimes if you're shooting something with a camera, uh, you know, depending on the quality of the lens, the quality of the camera, you may get an effect where the red, blue, and green parts of the image don't line up perfectly. Um, and I'm sure you all have seen this before. And it actually, when you use this effect, it, it almost makes your video feel like it came from the 1980s, because that was sort of the heyday of really crummy quality video. Um, so chromatic aberration is one of those effects that composite, or is a use to kind of beat up their perfect renders, right? You have is you have software like Maya and cinema 4d that gives you absolutely pixel perfect renders.

Joey Korenman (02:01):

And that doesn't look real because we're not used to seeing things that are perfect because nothing in the real world is perfect. So we beat our footage up. And one of the ways we do that is by having the red, green, and blue channels, uh, get a little bit out of sync. So I'm going to show you how to do that first and after effects. So we've just got a pretty simple little scene here. And you guys all saw the preview of this when you started the video, right? So you've got one cube, it kind of turns, there's a missing frame there, don't worry about that. And then it fires out and you know, there's some, some cloned cubes and it's this cool composition, but I set this up, uh, specifically for this tutorial because you've got some very thin white lines, right? And then you've got red, green, and blue colors.

Joey Korenman (02:44):

There's also some yellow, but, um, I wanted to show you a good example of, of a shot that would benefit from using chromatic aberration. So the first thing that you need to understand, and a lot of people who use after effects, don't really think in these terms, because one of the things I don't like about after effects is that it hides a lot of the technical stuff from you. It makes it a lot easier, but at the same time, um, it, it sort of, it's, it's kind of, you know, I don't know how to really put this, but it's sort of hiding things from you that if you knew they were there would, would give you more options with your composite, right? So one of the, one of those things is the fact that every image you bring into after effects has three channels, sometimes four, all right.

Joey Korenman (03:32):

And if you see this little button right here, right, and you, and maybe you've all noticed it, but I bet most of you have never clicked it. If you click this, you can actually see the red, green, blue, and alpha channel on their own. So let's look at the red channel. All right, you see how my viewer now has this red line around it? Okay. So this is a black and white image obviously, but what this tells after effects is how much red is in each part of the image, right? So over here, it's black. So that means there's no red over here and over here, it's a lot brighter. So that means there's more red right there. Now let's switch to the green channel, uh, the hot key to do this, by the way. Cause I'm a huge fan of hotkeys is you hold option and you hit two for green, three for blue, one for red, four for alpha.

Joey Korenman (04:20):

All right. So it's option 1, 2, 3, 4. And if you, uh, if you then hit, so if I hit option one and then I hit option one, again, it brings me back to my full RGB view. All right. So we're looking at the green channel. We're looking at the blue channel. We're looking at the alpha channel. The alpha channel is all white meaning there's no transparency in the scene. Okay. So now, um, you know, this just sort of demonstrates to you that your image has three color channels. Now they're all combined into this one layer. So how do we separate them out? All right. So the first thing I want to do is just color, correct this a little bit, um, because it's a little bit dark, you know, when you, when you render things right out of a cinema 4d, it's very rare that you're going to just leave them the way they are.

Joey Korenman (05:06):

You're almost always going to touch them up a little bit. Uh, and I'm not going to go too crazy here. I just want to show you some of the weaknesses after effects in the process of doing this. So I've color corrected it a little bit. I'm going to duplicate this layer and I'm going to set it to ad mode. And I'm just going to throw a fast blur on there really quickly just to get a little bit of a glow. Um, I'm going to zoom out and I want to mask. I want to mask my glow air just so it's kind of catching the tops of some of these. I don't really want the whole, the whole scene to have this glow on it. All right. And you can see I'm getting this little washed out area here. So on my glow layer, I'm going to crush the blacks a little bit.

Joey Korenman (05:52):

So that goes away. All right. So just got like a little, you know, nice kind of glow now on this. Right. Um, you know, and then maybe I want to add an adjustment layer so I can color correct this a little bit more. So I'm gonna add, um, a color balance effect. I'm doing this really quickly because, uh, you know, I don't wanna spend too much time on this for this part of the tutorial. Um, but I definitely think I want to do a full, really nice composite in after effects for a tutorial one day because, um, there's a lot of tricks to it that I've learned over the years, um, to get your renders to look really good. So anyway, we're going to stop here. We're going to pretend that this is what we want. Okay. So now I need to pre compose all of this.

Joey Korenman (06:36):

All right. And this is where after effects starts to make this a little harder than it should be. I have, you know, sort of a composite chain here. I've got my base render with some, some color correction on it. Then I've got a copy of that, that I'm blurring and adding over the original to create some glows. Um, I've got an adjustment layer that's working on, you know, my render and my glow. And it's just kind of, um, changing the colors up a little bit. Right. And I'm not too happy with how that's looking right now, but I'm going to leave it. So, uh, next, what I want to do is take the results of all of this. And I want to break it up into the red, green, and blue channels. And unfortunately there's no way to easily do that with these three layers, still separated out the way they are.

Joey Korenman (07:23):

So I'm going to have to pre compose them. So I'm going to select all three of them. I'm gonna hit shift command C to bring up my pre comp uh, dialogue. And I'm just going to call this, uh, image. Okay. All right. So now that this is all pre comped, we can now separate it into the channels. So let me rename this layer red. And what I'm gonna do is I'm gonna grab an effect and there's a group of effects called channel effects. And these are all things that, that work on individual channels or sometimes multiple channels. Um, and to be honest, I have not seen very many after effects artists use these, um, when I hire freelancers for toil, um, you know, most of them are sort of self-taught and when you self-teach yourself, it's kind, kinda like a, that was a really bad grammar right there.

Joey Korenman (08:14):

When you teach yourself after facts. Um, most of the time you're, you're sort of figuring out the quickest, easiest way to do things and using these effects is usually not the quickest, easiest way, but they're very powerful. So what I'm gonna use is the shift channels effect. Now, what is shift channels effect do all right. Well, if you look up here in the effect controls, it basically lets me switch, which channels are going to be used for the red, green, blue, and alpha channels. So this layer here has a red channel, right? And just to show you one more time, this is the red channel, the blue channel, sorry, the green channel and the blue channel. Okay. So what I want is to isolate the red channel. So what I'm going to do is I'm going to tell, so the red channels take is, is actually using the existing red channel.

Joey Korenman (09:05):

I'm going to tell it to take the green channel from the red channel and the blue channel from the red channel. Okay. So now I've got a black and white image, and if I switched to the red channel, now you'll see that nothing changes because this is the red channel. All right. So now let's duplicate that and let's call this the green channel and we're just going to do the same thing. We're going to switch all of these to green. So now this layer is only showing me the green channel. All right, now we've got the blue channel, so we'll do the same thing.

Joey Korenman (09:40):

Great. All right. So now these are separated out now, you know, the obvious problem is that this is black and white. Now this is not what we wanted. Um, so when you use shift channels and you switch all three channels to be the same, this is what the result is. It gives you a black and white image. So now what I need to do is turn this black and white image into an image that reflects the amount of red in each pixel. Um, so the easiest way I found to do that is to add another effect. It's in the color correction group and it's called tint. And it's really simple. And what tint does is it lets you, um, map the black, all of the black in your layer to one color and then map all of the white to another color. So all of the black should stay black, but all of the white, the white is telling after effects how much red should be in the image.

Joey Korenman (10:35):

So that white should actually be a hundred percent red. All right. Now, a quick note, if you'll notice I'm in 32 bit mode here, um, and that's because I rendered out open EXRs from cinema 40, with 32 bits of color information. Um, and so it's better when you have 32 bit renders to work in 32 bit mode and after effects, your color corrections will be more accurate. You'll have more latitude to, you know, to bring up dark areas and bring down bright areas. Um, and when you switched to 32 bit mode, these RGB values no longer go from zero to 255, they go from zero to one. Um, and so that confuses some people cause, cause a lot of people just leave after effects at the default eight bit, um, eight bits per channel. And if you're working in 32 bit, just know that the RGBs will look a little bit different.

Joey Korenman (11:29):

Okay. So, um, if I want a hundred percent red, then all I need to do is set green to zero and blue to zero. All right. And you can see, this is what it did. It, it made my red channel actually red. All right. So now I'm going to copy the tint effect, turn my green channel back on and paste it. And instead of a hundred percent red, we just do a hundred percent green just like that. All right. And you can probably guess what the next step is blue. Cool. All right. So we've got our red, green and blue channels and then the last step is you just set all of them to screen mode and there you go. So now we have our a and if I, if I jump in here right into my pre comp, you'll see that it matches up pixel perfect.

Joey Korenman (12:16):

Now here's the original pre-com with the render in it. And here's the comp where we've separated out the channels and they look identical. We've separated out red, green, and blue. We've put them back together. Um, and now we have the control to move these around. I can take the green layer now and nudge it and you can see that it's actually split and I can move it independently. So, you know, in reality, chromatic aberration generally works this way. Um, things that are in the center of the frame are aligned a little bit better than things on the edges. Um, and so if I just sort of move these layers like this, right, this is generally not how chromatic aberration looks. Um, although, you know, we're just, we're trying to make something look neat here, right? This is, this is one of those techniques that just sort of adds kind of a feel and a look to things.

Joey Korenman (13:09):

Um, so I generally don't worry too much about how accurate and effect like that is. Um, but if you wanted to try and reproduce sort of like, um, you know, chromatic aberration from a camera, then you could use an effect like maybe, um, optics compensation, right? And if I solo the blue layer to show you optics compensation, um, basically simulates lens distortion, right? You can see how this is sort of turning it into almost a fish eye lens or something. So, um, what you could do is reverse the lens distortion, and then it, it distorts it the other way. So you can see that the middle of the image does not move very much, but the outside moves a whole bunch. Um, so if I have an effect like that on the blue channel, and then I maybe do the same thing on the red channel, but I changed the values a little bit.

Joey Korenman (14:00):

Right. You can see that in the middle here. If I zoom in, in the middle, everything's lined up pretty, pretty well, but then on the edge as we start to, uh, we start to get some out of syncness here with the channels. Cool. Um, so that's one way to do it. And of course you can always, you can always just sort of nudge your layers around a little bit. Right. I could, um, I could just make the blue, you know, up into the left and then make the green down into the right. And you'll sort of get this out of sync. Cool looking, uh, cool looking effect. And it really works well if you have dark areas with, uh, with white things in them like this white grid here, because white is a hundred percent red, blue, and green. And so you're actually gonna, you're gonna really see the effect there.

Joey Korenman (14:51):

If you have things that are blue, right, then they're not going to have as much green and red in them. So you may not see the chromatic aberration as much there. Um, but you can see this, this image is kind of a good test image for this effect. All right. So this is how you do it in after effects. Now, Y you know, what's the issue with this, right? This works perfectly well. There's, there's no problems the, the, the issue, right? And I'll show you in a minute how to do this in nuke. And, and hopefully you'll see why nuke might be a better option for this effect. The problem with after effects is that I can see, I have a blue, green, and red layer, but I cannot see, you know, easily what is happening with the blue, green, and red lighter. If I, if I click on one of these layers, I can then see, okay, there's a shift channels effect.

Joey Korenman (15:42):

There's a tint effect, tinting at blue. And then if I click on the green, I can see that it's tinting at green, but I kind of have to click through these things to see actually what's going on. Um, I also just at a glance, have no idea which channels I moved. Right. Um, because I, you know, I would have to open up the position and keep this open to actually remember which ones were moved. If I had an optics compensation effect on here, like what I showed you, I wouldn't actually know what that effect was doing unless I clicked the layer that that effect was on. The other big thing is that let's say, I'm looking at this and now I decide I want to color correct it a little differently. Well, I can come back into this, pre-camp here and I can color correct it.

Joey Korenman (16:23):

And then come back here and look at the results. Um, of course, there's, there's other ways to work on this comp, but see this comp I could, I could turn the lock on, on the viewer, come back here and then, you know, change the adjustment layer up and try to try to get a little bit different of an effect, but it's kind of clunky. I have to go back and forth. Right. And, um, you know, let's say I wanted to adjust the mask on this glow. Well, I can't do that if I have the lock on the view, or I need to turn that off. Now, I need to come back in here and adjust the mask and then come back in here and see the results. So, um, this is where after effects starts to get clunky. And for those of you that use after effects a lot, um, I know, and I know that you know, that there are ways around that clunkiness and there are ways to composite in after effects and get the same result you get nuke.

Joey Korenman (17:14):

Um, I, I'm just telling you, once you get the hang of nuke, nucleus, just so much more elegant at doing things like this, right. I would never animate in nuke. Aftereffects is much better for that, but when you're compositing and that's what this is, we're taking 3d renders and we're trying to make them look awesome. Nuke is just better at that. All right. So that's how you do chromatic aberration and after effects. I am now going to show you how to do it in nuke. So let's switch over to nuke. Now I know, uh, that nuke is not as widely used. And so, um, the interface may look strange to you, and it's a node-based compositing application, which works a lot differently than a layer based compositing application. So I'm going to try and explain each step to you as though you've never used nuke before.

Joey Korenman (18:04):

So I apologize if you have used nuke, um, this is going to be a lot of review. So here is all, this is the only thing I have in this new script right now. Okay. First of all, nuke projects are called scripts. That's the terminology that's used. This is a new script. You have an after effects project, and you have a new script. So this right here, this is called a read note. All right. And a read node literally just reads in files. And if I double click this note, I see some options over here, right. So it's telling me which file. So these are my render files, um, CA underscore scene dot EXR. Um, and I didn't render this 16, nine. I did it a little bit wider than 69. So, uh, the format is nine 60 by 400. Cool. All right. So, uh, let's say we want to color correct this a little bit.

Joey Korenman (18:57):

Okay. So, um, in nuke, every effect, every operation you do, even things like moving an image or scaling an image, everything you do takes a node. Okay. So that's why it's called a node based application. So if I want to just, you know, brighten this image a little bit, right. What I would do is I would select this node. Um, and over here, you've got a whole bunch of little menus and all of these things that I'm showing you, these are all nodes you can select. Um, and nuke actually has a really cool way of adding nodes, um, where you just hit tab and this little search box comes up and you can start typing in the name of the node you want, and it will pop up and then you hit enter. And here it is. So a grade node in nuke is, um, it's basically like a levels effect in after effects.

Joey Korenman (19:50):

Okay. Um, one other thing to notice is that I have this node down here called the viewer. If I disconnect this, I don't see anything, this what I'm looking at here, this viewer area, this works the same way after effects viewer works, except I can actually see a node icon for that viewer. And I can connect that viewer to different things. And there's hot keys to do that. So I can look at my original footage or I can look at the footage after it's gone through the grade node. So let's grade this a little bit. Um, I'm going to adjust the gain and you'll find also the color correction tools in nuke. They're a lot more responsive. I mean, look how quickly I can, I can sort of mess with these things. And they're, they're a lot more, um, precise to gain works on a much narrower range of values.

Joey Korenman (20:38):

It works on the brightest values. Um, and then you can also adjust the white point in the black point, the same as you would in after effects. Um, and then what I really like about nuke has they make it really easy to add color to each of these settings here. So if I wanted, um, let's say the, the black areas of this image to have a little color to them, that would be this multiply setting here. So, um, you know, I can raise this up and down a little bit. Right. But I can also click on this color wheel. Right. And I can just sort of move it around until I find a color. So if I wanted it to feel kind of really, um, synthetic, I could maybe have it be somewhere in this greenish blue area. Right. And maybe that's too much, but, um, and, and then I could do a different color, maybe a complimentary color right. On the highlights. Right. So if this was the color I was using, it would be somewhere over here, somewhere in this reddish orange area.

Joey Korenman (21:41):

Cool. And then I can just, you know, color, correct things up and down, um, and, and try to find the look that I want. Okay. All right. And so this is starting to feel a little bit washed out. So I'm gonna leave this where it was, come back here and just add a little bit of a greenish blue color to the gain. Okay. So let's pretend that's what we want. All right. So now I can very quickly see the original and the result. Okay, cool. Now, um, okay. So what was the next thing we did in after effects? We added a little bit of a glow to this. So, um, you know, I've said before that the glow effect that's built into after effects is terrible. The glow effect that's built into nuke is actually pretty great. So if I run right, and you can, you can see why, um, you know, you use these nodes, it makes like a little flow chart.

Joey Korenman (22:34):

You have your image, it gets graded. And then it goes through a glow node. Okay. Now the glow node, uh, has a bunch of settings and I can up the tolerance so that it's not actually making everything glow. Only the only the brightest parts. Um, I can adjust the brightness of the glow. I can also adjust the saturation of the glow, which is cool because this looks a little too colorful, and then I can bring it all the way down, you know, and just leave a little bit of that color. It also gives me the option for the effect only. So I only see the glow and this is where nuke really shows its power. Okay. So what I'm going to do is I'm going to have, and I kind of, I want to step through this cause I want to make sure everyone understands what's happening here.

Joey Korenman (23:23):

I have my image. It's going into a grade node, which color corrects a little bit it's then going into a global node. Okay. And what I'm going to do is I'm going to add a node called merge. All right. And this is one of the things that, um, people who are new to nuke and who use after effects initially, you'll find it silly in after effects. If you have two layers and you put them both in your timeline and you put one layer on top of the other one, the one that's on top is composited on top of the one that's underneath it. And nuke, none, nothing happens automatically. So if I have this image, right, this color corrected image, and then I have this glow layer, and I want this glow layer on top of this image, I have to tell it to do that with a node.

Joey Korenman (24:08):

So the merge nodes, how you do that. So, uh, the way the merge node works is you have two inputs. You have a, and you have B and you always merge a over B. So I want to merge this glow over this grade. All right. And so now, if I look through this, you'll see that now my glow is composite stud on top of my image, and I can step through my comp and see every step that's happening. So here's the original shot. Here's the graded one, here's the glow. And then here's the glow merged on top of the grade. Now, why did I do it this way? Why didn't I just have the glow node right here? Well, the reason I did it this way is because now I have that glow separated out. And so what I could do is I could, I could do different things to that glow.

Joey Korenman (24:59):

Um, I could apply more effects to it, or I could add a roto node, right. And I could come in here, um, and change some settings on the roto node. And I'm not going to get too deep into it. Um, but basically a roto node is like a mask in after effects, right. So I can, um, you know, I can change some settings on it. And basically what I want to do is get rid of the glow on certain areas. Right? I only want that glow, um, to show up on a specific part of the image. And you can see that, uh, the mask tool in nuke also is really powerful. Um, now you can do this. Now. You actually can feather your mask, um, on a per Vertex basis. That's what this is called. Um, nuke has always been able to do that. And, um, I hope you're noticing how responsive this is to, there is no lag.

Joey Korenman (25:56):

Um, nuke is designed to work very quickly in after effects when your comps get too complicated, even moving a mass point like this, it starts to slow down, um, in the nuke that doesn't happen. So now let's look at what's happening, right? Um, we've got our original footage and let me turn this roto node off. Um, it gets graded. Okay. Then this graded version goes into a glow node. It goes into the roto node, right? And here's the difference glow node, the roto node knocks some of this away. And then that gets merged over. Okay. So if I turn the roto node on and off, and this is another great thing about nuke, I can, uh, select a node and tap the D key. You see how it exes it out? Okay. So now I can really quickly see with without right. That, okay. So this is with, and I've, and I've mapped out some of this stuff here, so it's not glowing down here.

Joey Korenman (26:49):

It's only kind of glowing in this area, which is what I wanted. All right. Now let's talk about chromatic aberration. Okay. So in nuke, nuke does not hide the channels from you as much as after facts. And, um, if you want proof, just look, I double click this merge note and look, I've got a list of all the channels are right here, red, green, blue, alpha, and you know, and so in nuke, you're always having to think about, do I have the channels set up correctly? Um, there's a lot more manual work involved in nuke to add an alpha channel to a red, green and blue channel, and then have that alpha channel applied correctly. And you, a lot of times a nuke, you're doing operations to individual channels. Um, so if we look at this merge node, right, this is the result of our composite so far, and I hold my mouse over the viewer and I hit R it shows me the red channel G is the green channel B as the blue channel.

Joey Korenman (27:48):

Okay. So this part works kind of the same as after effects. So the first thing I want to do is split those channels up. Um, so if you want to split channels out, um, from part of your composite, you use a node called the shuffle node. Okay. So here's my shuffled node. Um, and I'm going to connect this to my merge node, and I'm going to double click this, and I'm just going to call this shuffle underscore R so I can keep track. Um, and in the shuffle node settings, you'll see, you've got this interesting little, uh, grid here. Um, and basically what this is saying is these are the channels that are coming in right in, from, in, from one RGBA and using these check boxes, I can decide which channels to keep in which channels to get rid of. Um, so I want the red channel.

Joey Korenman (28:41):

I don't want green or blue or alpha. I actually want all of these to be red. Okay. So I'm just going to say all of these are red. And now if I look through this again, I've got a black and white image, right? So this is the red channel. Now I can copy and paste this node and connect this to the merge node. So what's cool in nuke is that you can have one node connected to a bunch of different nodes. So in after effects, we would have had to take all of this and pre compose it and basically hide it from ourselves. Then we could split it out into different channels and nuke this all doesn't change at all. And now you literally get this visual representation of what's happening to your image. Okay. So I'm going to switch this node to green. Okay.

Joey Korenman (29:27):

I'm going to paste it again. Let's rename this shuffle underscore B, and then we're going to switch all of the, uh, all of the channels to blue. Okay. So we've got red, green, and blue. Okay. And now I want to recombine them. Okay. So, uh, basically in nuke, if you put a red channel, if you put a black and white image in the red channel of a black and white image in the green channel and a black and white image in the blue channel, it's going to automatically turn them red, green, and blue. You don't have to do the trick that we did in after facts of tinting, this black and white image, and then screening it back over itself. Um, so it's nice like that new just kind of saves you a little bit of work, um, because it's designed to work with these channels.

Joey Korenman (30:17):

So what I'm going to do is I'm gonna use another node called a shuffle copy. Um, and I'm gonna first start with the red and the green. Okay. Um, and you know, you can see that, uh, you know, I'm kind of anal retentive, and I like to have, uh, all of my nodes kind of lined up and I like to try and keep the lines straight. It makes it a lot easier for me to visualize what's going on. Um, so sometimes, uh, if I'm moving a note around all hold command, and when you hold command, you see these dots up here and you can add little elbow joints to your nodes. Um, so if you're really kind of a geek and you like organizing things, nuke is for you because you can create these beautiful little trees. Um, and you, you know, once you've used nuke a little bit, you'll look at this and you'll be able to see exactly what's happening.

Joey Korenman (31:07):

This is the biggest advantage of new Kovar after effects is you can see every single thing that's happening in your comp all at the same time. Right? So it's very clear to me that I have footage it's being affected. And then I'm splitting the result of that in two directions. One direction goes this way and I can say, oh, that's going into a glow node. And then that glow node is being merged over the original results. And then that results being split into three things. And you can go in and since I've labeled these it's clear, oh, I'm making a red channel green channel and a blue channel. So there's no jumping back and forth between pre comps. So in this shuffle copy node, um, what I want to do is, um, keep the red channel right from our, because if you look closely, you'll see my shuffle copy has, uh, two inputs.

Joey Korenman (31:59):

One is labeled one, one is labeled two. And so what I'm telling nuke is from input one, which is the, the red channel, keep the red channel from input two, which is the green channel, keep the green channel. And when we're not, we don't care about the blue channel yet. Okay. So it doesn't matter. What's checked there. In fact, I could turn that off. All right. So we're keeping the red channel from one, the green channel from two, and now I need another shuffle copy. Okay. And I'm going to connect this up to the blue channel.

Joey Korenman (32:32):

All right. So now input one. We want to keep the blue channel and input two. We want to the red and the green. Okay. All right. So now, if I look through this shuffle copy node, this final one, right. You'll see that I've got my image. If I look through this merge node way up here, this is where we started. Okay. And then we did a bunch of little operations here to break, break the image up into channels, and then put them back together. And at the end of that, we're left with the exact same image. Now here's, what's great is that I now have these little tree trunks here with no nodes on them for red, green, and blue. And I could very easily add a node, let's say a transform node. Okay. So this is one of the things when I started using nuke that I thought was silly.

Joey Korenman (33:22):

If you want to move, um, an image, uh, or scale it or rotate it, or do anything, you actually have to add a node to do that called transform. And it seemed like a lot of extra work, um, you know, and in after effects, you would just click the layer and move it. Um, so why do you have to use a node and nuke? Well, if you use a node, there's a lot of cool things you can do. Um, and I'll show you a couple of those in a minute, but let's just add this transform node. Double-click it. And over here, you can see all your settings for the transform node, and I can click and drag this around, just like this. Okay. Um, that works just the same as after effects. And, uh, but I'm just going to nudge this a few pixels on X, all right.

Joey Korenman (34:06):

A few pixels on a Y and you can see we're getting that same chromatic aberration effect that we had in after effects. So now I can copy this. So I've copied and pasted the transform node, and I can, you know, adjust this one a little bit differently. Right. So, uh, you know, the red channel, I've moved in one direction, the green channel I've moved in a slightly different direction. Um, maybe the blue channel, um, we can add another transform node and we could just scale it a little bit. Right. And, um, one of the things I really like about nuke is that you can, um, you can just use the arrow keys really quickly to get very precise with, uh, with what you're doing. If I, if I move the arrow, if I move the cursor to the left, then I'll, I'm working on the, um, you know, on the tenths digit here.

Joey Korenman (35:01):

And then if I hit right arrow, right. And now the cursor's moved a little bit and now I'm working on the a hundred stitches, so you can get really precise and I can even hit right again and now I'm working in thousands. So you can very quickly dial in exactly the value you want for this. Um, cool. All right. So now we've got chromatic aberration, and we're good to go, right. And look at this. This is so much more clear, um, at least to me, and I hope it is to you too. It's very clear what's going on here. Right? You've got, um, you know, you've got your merge node and it's being split into three channels and you literally get this visual of what's happening and then they get put back together. And then once they've been put back together, then you can do even more stuff.

Joey Korenman (35:45):

So you could add a lens distortion node. Okay. And this is sort of like optics compensation in after effects. And you can get some really nice lens distortion out of this. Cool. And then maybe we want to add some film grain to it. So we would add a grain node. Um, and we could, you know, there's, there's some presets here that Newt comes with. You can also, um, really dial in the intensity of the red, green and blue channels. Um, and there you go. And so now here's your composite. Okay. And, um, if you, if you look at it and let me just make this composite full screen for a minute, if you look at this, you can see every single step of your composite in one view. And once you've used nuke a little bit, and you sort of start to recognize, you know, there's kind of a color scheme that nuke uses, um, for these nodes.

Joey Korenman (36:38):

And you'll start to recognize, okay, a blue node is a merge node. A green note is a rodeo note, and this color is for shuffle nodes or shuffle copy nodes. Um, and so very quickly, even if I didn't know what the result of this was, I would be able to tell you, uh, okay, let's see, you've got a render. And then there's a glow applied to it. Um, that glow is massed out a little bit. We're clearly splitting the image into red, green and blue channels here. There's transformed nodes. So I know that you've moved them. Um, and then you've put them back together, there's lens, distortion, and grain, and you can see all of that right here. You don't have to click on layers and know what effects are on them are going to concert any of that. Um, and there you go. And so, and you also saw how responsive this is to like, if I, if I say, okay, you know what, I want to step through every step of this composite that I've done, you can do that.

Joey Korenman (37:32):

And an after effects, it would be very tedious to do that. Here's my render graded. Here's the glow that we set up and then massed out and then merged back on top of the image. Here's the red, green, and blue channels, and we've transformed each of those. Right. And then put them back together to get chromatic, aberration, added lens, distortion, and grain. And it's that quick. And you can see how quickly this renders too. Right. I'm stepping through this and it's rendering every frame and it is literally going that fast. You can almost scrub through it. Okay. So for stuff like this use nuke, it's just a lot better. Um, the last thing I want to, I want to mention about this, um, which is one of the things that I'm starting to do more and more of a nuke. And I think it's really awesome and really powerful.

Joey Korenman (38:20):

Um, so let me hop back into after effects for one second, let's say that I really love this chromatic aberration effect. I think it's the greatest thing I've ever done, and I want to save it as a preset. So how would I do that in after effects? Um, well, you really can't, what you could do is save this project as a setup. And basically you'd have to load that project into whatever new project you're doing, go into one of these pre comps and inside of the pre comp, replace that with whatever image you want and then come back out to this comp, and this is where the chromatic aberration happens. Okay. But there's no way to put a render in and apply chromatic aberration effect with what's built in to after effects. Of course there's third-party effects and scripts, and you can go buy things.

Joey Korenman (39:12):

Um, but to be honest, if you're buying an effect to create chromatic aberration for yourself, then you're throwing your money away because I just showed you how to do it for free with what's built into after effects. Um, and it's not hard at all. So you really should not pay someone to do this for you. Um, now let's look at nuke on the other hand with nuke, um, I'm, I'm going to change one little thing here. Okay. So I've got this merge node and it's being split into three different pieces here. What I'm going to do is I'm going to add an elbow joint to one of these, and I'm going to connect these other two, uh, shuffles to the elbow joint. Okay. And the reason I'm doing this. Okay. So what I have now is basically this section here is a self-contained set of nodes, right.

Joey Korenman (40:01):

That actually create chromatic aberration for me, all of this stuff that happens before this is just color correction in some glow. And then at the end, this is lens distortion and some, uh, some film grain, but this, this is chromatic aberration. And what's amazing about nuke is that I could right. Click this whole setup. Right. And I can go to, um, I can go into the menu here and I can actually group these nodes right. And say collapsed to group. Okay. Um, and actually I must have not had them all selected. So let me select them one more time. Okay. I'm going to try going up to edit node group collapsed a group. Here we go. Okay. So now what just happened, right? All of those nodes that created chromatic aberration are now inside of one node. Cool. And if I, uh, if I click on this group here, um, I can rename it.

Joey Korenman (41:00):

I could call this chromatic aberration. I'm not sure I spelled that right. Either someone spellcheck me. Um, and then I can click on this and actually bring up a little node tree for just that group. Okay. And let's look at this. You've got input. One input. One is basically, whatever is being fed into this group comes in here, gets split up into red, green, blue gets transformed a little bit. And then that gets put back together and sent to this output node. Right? And now if we switch back to our main node graph, you can see whatever comes into this group comes out, split up with chromatic aberration. So I can actually select this node now. Um, and I could, I could copy and paste it and put anything I want into it. If I make a, like this little checkerboard pattern, and I run this into the note and look through the node, I've got chromatic aberration now.

Joey Korenman (42:02):

And I have basically built myself an effect in like two minutes. And what you can then do is you can select this node and keep in mind, this node is just a group of nodes. Um, you can select it edit node group, and you can actually, um, you can actually turn this into what's called a gizmo. A gizmo is basically the nuke version of an effect. Um, or, or maybe it's more like the new version of a script. Um, nuke users can, can make groups of nodes and you can get really, really complicated with it and then group them together. Um, and you can even go as far as creating some controls on them using some new, you know, nuke expressions. Um, but you can actually turn these into something that you can, um, that you can, you know, share. You can upload these, uh, you can send them to other people to use.

Joey Korenman (43:00):

And you've got this great effect in one little node that in after effects would be impossible to turn into a one click kind of effect, right? You have to break it up into pre comps and do a lot of work. So that is one of the coolest things about nuke. You can have really complex kind of setups that then you can reuse really easily. Um, and at the same time, look at this comp. Now let's take a look at this comp. Now that I've grouped my chromatic aberration into one node, look at how simple this is. Right? My after effects comp that I had two pre comps and I had three copies of, of a, of a comp and I had effects on each one and some of them were moved and some of them weren't, this is just so crystal clear, right? And there's, you know, there's like less than 10 nodes here.

Joey Korenman (43:49):

It's just like so simple. Um, and I'm getting the exact same effect I got in after effects and it's rendering significantly faster. Um, so, um, I hope I didn't go through this too quickly because I know nuke is brand new to a lot of you. Um, this was not a, you know, beginners, nuke tutorial. This was sort of in the middle somewhere, but hopefully even if you've never used nuke and you didn't fully understand every step, you were able to follow enough to see the power of nuke and why nuke, um, is designed the way it's designed to why that's useful for compositing. So, uh, I hope this was interesting to you guys because, uh, I think learning nuke is one of the best ways to expand your capabilities and expand your employability and your marketability, um, and, and add a whole new set of tools, um, you know, to your arsenal and, and be able to, you know, get more clients and make some more money, do more work and, and, you know, pay the bills, provide for your family, buy a house, buy a car, do whatever you gotta do.

Joey Korenman (44:57):

Um, once again, Joey from school motion. Thank you guys. And I'll see you later. Thank you for watching. I hope you learned something new about compositing, your CG renders in after effects and nuke. They're both very powerful programs and this lesson should have also given you a good idea of what the differences are between the two programs for compositing. If you have any questions or thoughts, let us know. And we'd love to hear from you if you use this technique on a project. So give us a shout on Twitter at school of motion and show us your work. Thanks again. And I'll see you next time.