After Effects Weekly

– [Eran] Hey everyone, and welcome to After Effects weekly tips. My name is Eran Stern, and in this episode, I want to share a simple technique that will help you to pull better keys inside After Effects. To demonstrate this, I have this composition that was originally created by my talented friend Eyal B. You can check more of Eyal’s work at eyalb.com. So here we have some layers waiting to be keyed and composited over this moving background.

I want to concentrate on pulling the best green screen possible. So I’m going to pause the playback, and I’m going to start by selecting those two guys. I’ve already masked the unnecessary areas, and I’m going to zoom in so we can get a sense of what we’re doing, as closer as possible, in this case 100%. So our starting point, as always, is to go to the Effect menu, and then under Keying, select the Keylight effect.

And I’m going to take this eyedropper, and just click somewhere in order to pull a key. Now as you can see, this is probably not the best place to key, due to the fact that we have some leftovers. And in order to demonstrate what I mean, I’m going to switch the view of Keylight from Final Result to Screen Matte. Now obviously we can open up the Screen Matte and start to crush the black, and the white, until we get something decent.

And this is obviously a great way to work, but the thing is that we are losing some of the dynamic range between the black and white. So instead, I want to try and pick a better color in order to get more details out of this image. So I’m going to start by resetting the plugin, and then I’m going to sample the same green that I started with, but this time, I’m going to switch the view from Final Result to the Status mode.

And this is going to show us three colors. White, which is completely opaque, black, which is completely transparent, and gray, which has some sort of transparency. Now in order to get a better starting point, I’m going to click on the green color over here, which is going to show me the color picker. Make sure the Preview is checked, and then I’m going to start and move this green until I see something which is giving me a better starting point.

Now obviously we still have some work to do, but we are starting from a much better place. Now if I’m going to go to the Screen Matte once again, we can see that all the black parts of this image are basically being handled by selecting the correct green, and all we need to do is just give a little bit of treatment to this Clip White. And now, if I’m going to switch back to the Final Result, we have something which consist of much more details.

Let’s do it again for the lady over here, her name is Avital. I’m going to select her, I’m going to apply the Keylight effect, I’m going to click in order to sample this color, let’s just move a little bit so we can get a sense of what we are doing. Once again we can see some leftovers and noise. I’m going to switch immediately to the Status view, click on the color chip, and then move this green until I find something which looks a little bit better as a starting point.

So I’m going to guess that you will never think of keying this color, because you basically can’t see it. But in terms of what After Effects is seeing, this should yield a better result. Alright, let’s move to the Screen Matte once again, open up the Screen Matte controls, just play a bit with the Clip White, not too much, and then we can set it to the Final Result and check how everything is looking. And I think, this is looking great. So just to finish up with this shot, I’m going to enable those shape layers that are acting as shadows underneath the actors over here.

I’m also going to add some smoke detail, as well as particles, and also a general color correction. So everything is going to look more connected and more coherent. Let’s zoom out, go to the start of this comp, I’m also going to press on the tilde key in order to enter the fullscreen mode, and I’m going to press Spacebar to check the result. And this is it. Now keying obviously is a subjective task. You should always judge what will give you a better result on a shot-by-shot case.

But I think that when you start the process correctly by choosing the best color to key, the rest of the modifications will make more sense and should work much better.

Source After Effects Weekly