Transforming Robot Production Pipeline Volume 10: Compositing

In this lesson, we're going to learn how to create animorphic-like lens flare effects inside of Nuke with the Glint node, as well as some processing. So here's where we left off. We have a beginning of our flares on our transforming robot. But now let's add in an effect I really like, which is a lens flare based off of an animorphic lens. Now you'll know something is shot animorphically if the Bokeh, or the depth of field light artifacts, are taller than they are wider. Now we're not going to be doing that because most of our frame is in focus. We have a very wide depth of field here. But another feature of this lens type and this film processing is that over bright lights tend to leave horizontal bright streaks. Now you've seen this in films such as Star Trek, where the director, J.J. Abrams, used quite a lot of these lens flare effects. And it just adds a lot of depth to the scene. So to do this let's begin by dropping in a Glint node. And let's connect this up. Take a look at this. And initially, of course, without any changes and without formatting or processing our data, it's going to look a little strange. Now initially this Glint is a vertical Glint with two rays. So the light, or the color, is being distorted in the vertical channel. Now if we want this horizontal, we can change this rotation to 90. And this will now give us that horizontal Glint that we were looking for. However it's still very short. So we can come in and increase the length by quite a bit. I'm going to bump it up to 500. Now this, of course, is not the effect we're looking for. We do not want to take the entire composition and create this Glint on it. Now we currently have a tolerance value set up to allow us to sort of reduce the area of the Glint. And as we reduce this down, we use the entire image. But instead of this, let's actually connect this into one of our keyers, which is the Luma Keyer we created earlier. And let's actually connect this to the premult part of that node. Now you'll notice this effect is very, very rough to begin with. To make this look better, we can increase the number of steps that we are taking to generate this effect. Now once we have this Glint created, let's merge this on top of our original footage. And again we're going to need the lower this mix down quite a lot. And we're probably going to want to modify this Glint to make it a little bit cleaner and a little bit less strong because currently it's rather strong in this case. So to lessen this again we could come in and either modify our key, or again increase this tolerance. So let's actually increase this tolerance just a little bit to dial back on some of these areas with high Glints. So let's do something like, maybe 0.98 will give us a good value. And if we do not want the original footage there, we can turn on this effect only, which will remove the original pieces of this. And only leave us with this Glint. So now we've dialed that back a bit, this is looking much nicer. Actually, I still would like to reduce it even further. This is another effect that we want subtle and not to draw too much focus to. So we can lower this down even further. And we're going to be careful at the beginning of this because this can cause distortions. And even the slightest Glint can cause, or can create, almost an unreality in the scene. So at the beginning, in the first 50 frames, I don't really want any of this effect. So let's go in and let's key this at zero. And then later on, when the transformation is happening, let's key this back up to-- I'm not sure what value we had, 0.1-- to have this effect be subtle and not too overpowering. Now for this effect, what I was really looking for is the eyes. I really want the eyes to blow out. And I want the eyes to glow and be the focus of this shot. Now normally our view is attracted to the eyes in any shot. But in this case, I really wanted them to light up and have a very strong Glint and a very strong effect here. But with our default settings, you'll notice it's not really having that kind of an effect. So let's begin fixing this by grabbing our eye layer, or the lights layer with a shuffle node. So let's take a look at this transform here. Let's see if we still ever channels intact. That we do. And if we look at our lights, we still have those intact. So I'm going to shuffle our lights into the RGB. So let's grab our lights layer. And now we have just access to the lights of our render. Now I don't really want these other lights in here, the headlights. I just want the eyes. So we could either do some roto, or we could use an expression. So in this case, I'm just going to grab an expression node. And let's set the red channel to be red minus green plus blue. So if you want to remove white, or if you want to remove these gray casts, you can set these channels to the specific color minus the addition of the other two colors. So we can do red minus green. And in the red channel you'll notice that mostly isolates our eyes. We still a little bit of visibility here. So we can do red minus green plus blue. And that will remove that almost entirely. Now we will have some negative data, so it's important we clamp this. Because we don't really need data below zero in this case. We really only want the eyes. Now let's take these eyes and let's merge them on top of this premultiply. So I'm just going to drop a merge node in here, add them on top, so that our eyes are now included in that Glint calculation. And let's take a look at these. Still too subtle. So let's actually use this as a mask to really bump this up. So let's go over here and let's really gain these eyes up quite a bit. And again we're only interested in the red channel. So let's take a look if this is adding to it. Yes it is. So let's actually take this clamped value. And let's use this as a mask for this color correction. So that way, we're only blowing out the eyes. And instead of the alpha we want to use the red channel. Again, we're just interested in the red channel. So in this merge here, I'm not really wanting to add in the a green or blue. I just one this red channel to shine through. All right. So let's take a look at this, see if our Glint updates. Give it a second here. And if you're still not getting the look you're going for, take a look at the surrounding areas and the surrounding values. And then measure that. And then let's color correct the eyes to that value. So let's take a look here. And this is at about one. And this is about at four. So it should be giving us the colors we're looking for. Let's take a look at this Glint. And I believe our tolerance is actually causing the problem here. So let's lower that just a little bit to reintroduce that red there. Or we could, of course, come in and continue to increase this color correction to continue making that stronger and stronger. So now we can see we've dialed it a little bit too far. But I do like that color. Or I do like the intensity of it. So let's just clamp this again. Except this time, let's actually raise the white value to some other value. Let's try five. That's a little strong. Four isn't strong enough. So let's try 4.5. It's getting better. Even that's maybe a little bit too much. Let's try lowering this down to something like three, and again going to our Glint and lowering our tolerance. I want it to be visible, but I don't want it to overpower the rest of the image here. OK, so that's looking pretty good. Now of course we can play around with the length. We can play around with all of these values to create different animorphic looks. Now we could also use the Glint node with more rays to create these other type of objects. So with six, it gives you a star pattern. But I like the two, or the animorphic, look that it's giving us here. Now in this case we also piggybacked off of another luminance key. So we could drop in another one of those and customize this Glint even further. And actually, I want to do a little bit of color correction on this. So let's add in a color correct node here. And it's a little bit too even. So let's gain up our highlights. So let's gain up the bright parts of this. And let's pull down our mid tones a little bit. And this is going to give us sort of a fall-off shape like this, sort of like an ellipse, where the main focal points of this are very bright. But the Glint begins falling off much, much quicker than before. And of course we can dial this in however we want. One more important thing about Glint is you'll notice that it's increasing our size of our composite incredibly large. So after a Glint node, always drop on a crop node to bring your view back to its normal size. And make sure that you're not processing more pixels than you need. For that matter, it's also important to add the crop after our directional blur and our earlier blur, which is where our larger bounding box was being created from. So a few crops in a few key places will keep our scene nice and light and allow us to quickly and easily preview our image. OK, so now we have that done, we can jump to the next lesson where we're going to take a look at Camera Shake and how we can add it inside of Nuke and use it to create the effect of impacts whenever this incredibly large and heavy object hits the ground. Well if we had timed it correctly, and had everything done in pre-production, it would be great to actually shake the camera at the exact moment that the creature, or that the transforming robot, hit the ground. But instead we could, of course, add it here in post and maintain control up until the very end of the pipeline, as opposed to adding it in during principal photography or principal shooting, where you're kind of stuck with whatever you shoot. So in the next lesson, we'll take a look at adding Camera Shake.