Join Ian Robinson for an in-depth discussion in this video Getting started with Keylight, part of After Effects CC 2013 Essential Training.
The process for creating a successful green screen key has definitely gotten a little bit easier as time has moved on. In, this video and, actually the next few videos for this chapter, we're going to use three effects to actually pull a very clean green screen key. And we'll start by applying those three effects by using one of the effect presets. So let's select layer 1 in the timeline and go to the effect and presets panel. In that panel I want you to open up the options for the animation presets and then scroll down to the Image utilities folder.
In there, if you scroll down, there are several different keying options, and the one that I want you to choose is this Key Light option. Now since we can't read it, I'll go ahead and just make it a little larger. See it's going to apply a Key Light, key cleaner and advanced spill suppressor. So to apply all we have to do is just double click on that preset. As long as we have layer one selected it'll automatically apply that preset in the effect controls panel. Okay I'm just going to make the right side of the interface a little smaller here so we can see what's going on. Now the beauty in using this preset is the fact this screen color is automatically linked through these two other effects.
Through expressions and they're already set up. So all we have to do is click on the eye dropper for the screen color. Now, usually when I'm keying a color, like green or blue in the background, what I like to do is find the darkest area. So down here I'm just going to click, not right next to her body but, pretty close to her left arm here, so I'll just go ahead and click on the green, and that will go ahead, and pull the green key. Now you might think this looks pretty good straight away, but what you need to do is change the magnification up to 100% in the lower left corner of your composition panel, and then just press the space bar to kind of move around.
In here, you can see it's a little soft up here and I have a little bit of a green bleed that's happening here and it's a little soft in the, in the right area here. Since we have three different effects applied, if you want to toggle the original footage on and off, I would just suggest going to the timeline and toggling all of the effects off and on. So here, you can see that her hair is right here in this one, a little area. So. I'll just go ahead make sure my effects are on. Now another way to view how this key is happening is to click on this view pull-down.
Now, I'm going to make my effect controls panel a little larger so you can see all the words. Notice, the first option is intermediate results. And this is actually what we're going to use to have the information flow through the effect control panels, and go to the key cleaner, and then down to the advanced. Spill suppressor which notice isn't currently active. Though, I always want to switch back to the intermediate results if you click on that pull down and change it to Screen Matte, this will give you a black and white representation as to our key and if you look up here, you can see it's total really good job getting the fine details of her hair.
But on the lower left side over here you can see I've got some gray areas and that means they aren't going to be completely opaque they are going to be semi transparent and if we scroll down to the lower left corner here if we zoom in I'm just scrolling on my mouse wheel. You'll see that there's a little bit of noise here in the black area as well. In order to adjust this since we're viewing in the screen mat, we want to go to the screen mat area and Key Light. So let's open up screen mat and we want to adjust the clip black options and the clip white options.
So we'll work from the top down. I just want this to be a minute adjustment, so I'm going to go ahead and change clip black to a setting of about 12. Notice that got rid of all of these options, these little extra grey pixels over here. Now notice when I press the spacebar and move up, now you can really see that the grey pixels on the other side. So let's go ahead and decrease the value for clip white to around 94. Notice that's going to do a pretty good job of clipping off a lot of these grey values. You may still see one or two in there. You could clip it back just a little bit more.
Here, 89. That gets rid of that last one. Now notice the edges are a little bit what I would call chunky. So we need to actually make some minor adjustments to this, now in the past I would suggest making all of the adjustments within Key Light filter. But since we have this wonderful preset. All we have to do is switch our view back from screen map to intermediate results. It will take a second but it will refresh the scene. And I'll just go ahead and change my magnification back to 100% so I can get a more accurate representation as to what's happening. Now let's scroll down and instead of making adjustments in Key Light.
Let's go ahead and look at the key cleaner adjustments. If I toggle key cleaner off, and then on. Now if you look closely it looks like it's actually adding noise in the shoulder area, and at the top of her head. But if I turn that on, and you look closely, what it's actually doing is bringing detail back into the edges of her hair. So I'm going to change the magnification back into 200%. And just space around so you can really see the difference. If I turn that off and on, here you can see all that detail around the edges. Now I know I'm seeing some of this green, but that's where the advanced spill suppressor comes in.
And one of the things we can do is harden up the transition that happens between the key and the background, and the way to do that is to increase the alpha contrast in the key cleaner. So this is going to be another minute adjustment. Just click and drag to the right here and I'm going to increase this up to around 15%, and notice just making that one adjustment I've got a little bit sharper edges through the edges of her hair here. I do want the strength to be a little bit less cause it is kind of harsh. So I'll go ahead and decrease the strength down to around 81 percent.
And now if we look at her shoulder region, you can still see some of that hair that was there but it's not super noticeable. If I turn it off and turn it on, you notice this did a really good job of smoothing out that chunkiness. Using the key cleaner now another way to smooth out the is to enable reduced chatter this increases the render time a little bit but it does a good job of making the edges not sort of vibrate as we move. Through the different frames, so go ahead, and enable reduce chatter.
Now in order to remove this grain around her hair what I'm going to do is just move up to the top of her head. That way when I enable advanced bill suppression you can see her hair actually comes back to her normal color, and things look a lot better in terms of the key, because I've got all that detail back in, and it is the proper color. Now render shoulders, it is a little bit wider, the mat's a little bit wide. So we could shrink the mat just a little bit. I could say, minus point five and shrink that down just a little bit by pressing enter.
And that's just going to tighten up the edge just a little bit there. And that is one last adjustment I did within the key like effect. So, let me go ahead and click on the magnification pull down, change it to one hundred percent. And I'll just go ahead and preview what we have, after I make the screen a little bit larger so you can see everything that's going on. There we go. So let's go ahead and load up a RAM preview. It may take a second to load the RAM preview, and actually, I had Skip Frames on, so let me change that back to 0, I'll go back to the beginning and load up a RAM preview here.
There we go. So when you're doing a preview you want to make sure your viewing things at 100% magnification at full resolution and your not skipping any frames. That way if there is some weird chatter or advance movement that's happening around the edges, you will be able to see it before you go to render your project. Now up here in my info panel I can see how many frames have actually loaded. And once it gets up to around 30 frames. I'll just go ahead and press the spacebar. So we can preview. And as you can see the key actually looks pretty darn good.
And the detail I'm getting around the edges of her hair is excellent. Now in my personal opinion this is an amazing key because it's actually keying on H264 footage. Which is much harder to key, because of it's high compression ratio. It's really important to consider the quality of the footage that you're going to be keying when you go to actually pull a green screen key. You'll want to work with as little compression as possible. So definitely try to get an uncompressed format like Pro-res or Avid DNX HD or Apple lossless Quicktime.
Something that isn't as compressed. Obviously, if you can get a raw footage, that's even better. But once you have considered the footage that you are going to be working with. When you go to pull a key don't just slap Key Light on there and try to do it all in one plug in go ahead and go to your effects and presets panel and use that Key Light preset that will automatically load Key Light Key Cleaner and advances spill light suppressor
- Video terminology
- Creating your first composition
- Using layers, masks, blend modes, and track mattes
- Parenting objects
- Building complex objects with Pre-compose
- Exploring the ray-traced 3D renderer
- Understanding the order of effects
- Creating 3D projects from Illustrator files
- Lighting a scene
- Animating type on a path
- Using Keylight for green-screen footage
- Archiving projects
Skill Level Intermediate
Q: This course was updated on 6/18/2014. What changed?
A: We added new movies to the "Fundamentals of After Effects" chapter, reorganized and re-recorded the "Up and Running" and "Keying Green Screen Footage" chapters, and added new movies on Color Finesse 3 and masking individual effects.
Q: When I try to open a project file, After Effects tells me I need to update my system, since the file was made with version 13.0. But I already installed the most recent After Effects update. Why can't I open the project?
Q: This course was updated on 11/03/2014. What changed?
A: We updated 25 movies to reflect changes to the Creative Cloud 2014 release of After Effects. This includes the new optimized user interface and enhanced Cineware and CINEMA 4D Lite pipeline. The new movies are labeled with the "(CC 2014.1)" tag.