Don't have a green screen? No problem! Key out green screen footage shot in imperfect conditions with just a cell phone and a green shirt.
Let's face it, we don't always have access to perfect green screen setups but that shouldn't stop us from being able to use green screen footage in our projects. In this tutorial, I'm going to show you tools you already have available to shoot some green screen footage and then key it out with pretty decent results.
The first thing we need to do is import our green screen footage. To do that, go to file, import. Drag the footage to the new comp button. As you can see here, I have some green screen footage that I took with my cell phone, handheld, in front of a green shirt that I just held up, in the air, did not use any special lighting, have lots of wrinkles. This is pretty much the worst case scenario when you are trying to do a green screen. But I'm going to show you how you can key it out pretty simply with After Effects.
In your Effects and Presets window type in key. Then what we need to select is a single instance of the Keylight plugin. Drag it onto the clip. Get the eyedropper by screen color, then select a color that's near the object you want to key out.
For this technique we are going to use two keylight effects. For this first effect we just want to get a really rough instance of the figure or the object, so we can be very aggressive with our effects.
The first thing to do is to click down under Screen Matte and then also show the Screen Matte Result. What we want to do is clip the black levels pretty aggressively till we don't have anything in the background and then clip the white levels pretty aggressively so there's nothing remaining here.
We can clip the black more to get rid of this spot right here, so I'll do that. Because this is an imperfect shot, no amount of black clipping will get rid of this section. But we can easily get rid of that by using a garbage matte. So I'm going to do that with the pen tool. Draw out a mask with the pen tool. Notice everything disappeared. That's fine.
We can twirl out the layer and under masks, Mask 1, we can say subtract. Now switch from Screen Matte to Intermediate Result. Not a bad key but we want to do is improve it even better with less aggressive clip black and clip white. To do that we are going to expand the matte with a choker.
In Effects and Presets, type in choke. Drag simple choker on to the clip, and then type negative 100. This brings a matte edge out from the original alpha channel of the original keylight. Down here we are missing just a little bit. We can just duplicate it by pressing command D and notice that I get more of that hair down at the bottom there. This may or may not be necessary for you.
In the timeline, right click and pre-compose. By default when you are selecting a single layer it will say "leave all attributes in the main comp" we don't want that, we want to move all attributes into the new precomp. We want to relabel this, Garbage Screen. Now all of those effects are inside this Pre-Composition Garbage Screen.
Now go back to Effects and Presets and type in key. We want to use the animation preset, Keylight, Key Cleaner, and Advanced Spill Suppressor. Drag it onto the footage. This time once again we will click on the eyedropper somewhere near the footage. And now what we need to do is instead of screen matte, because if we click screen matte it will show both mattes, what we want to do is show combined matte, that way it will add up the different mattes all together.
One thing that sometimes is helpful, you see how we can see some green here? You can double click and move this around just a little bit to see if it makes any difference to get a better key. Now twirl out Screen Matte and we can clip the black levels then we can clip the white levels, What we want to do is check a few other places to see how this is working.
If you notice up here, I still have some black to clip, so I'll do that. Now switch to Intermediate Result. This is a pretty good key. What we need to do now is click Advanced Spill Suppressor, and there we go. Press N to change the work area, and do a RAM preview by pressing space bar.
As you can see, we have a very good key even though we didn't spend anytime to set up a green screen. Let's add a new layer to show off the effect of our green screen. I'm going to move this layer below our footage, then let's set some keyframes. Press P then hold shift, then press S. Drop a keyframe by pressing the stop watch, then move forward, move the text to where we want it to end, hold shift to drag back to the other keyframe. You can also press the J and K keys to toggle back and forth to keyframes. Here, let's make the scale zero.
Now we have animation that can exist behind our figure all keyed out. Who wants to be stuck with a cheap green screen when we can go to the ocean?