How to Chroma Key in Adobe Premiere Pro
You can chroma key your video footage in Premiere Pro without sending your clips to After Effects. Keying in Premiere Pro is simple and effective.
Chroma keying is usually something that is done in After Effects, but sometimes, whether the simplicity of the project or just the fact that you do not want to send your footage to After Effects, you’ll want to chroma key in Premiere Pro.
This is Dan. He’s about to get chroma keyed.
Premiere Pro comes with a great keyer built right in called “ultra key.” Ultra Key was introduced to Premiere Pro in version CS5, so if you are using a version prior to CS5, you won’t be able to use this tool.
First, we’re going to apply a matte to our footage to get rid of the excess parts of the frame. I usually use “16-point garbage matte” to my footage and move the points loosely around my subject. If your subject is really simple, you can get away with only using the 8-point garbage matte.”
You’ll have to click the effect in your “effects controls” window to be able to move the points around.
Adjust the points around your subject.
Now that we have our frame trimmed in a little bit, we’ll apply the effect, “ultra key.”
Once we’ve applied the effect, in our effects controls window, select the eyedropper tool. This is how we select our green chroma color. Now, click the green screen with the eyedropper. Choose a point that is close to the subject’s face. If your greenscreen was not lit well you may have to choose either a lighter or a darker shade of green in your clip. If this is the case, choose the darker shade. This will make it easier to get a perfect key.
Click the eyedropper to choose your chroma color.
Select a shade of green with the eyedropper tool.
Now, change the output view to “alpha.” This will help us see the detail when we’re adjusting parameters.
Select “alpha channel.”
This is a view of your alpha channel.
If your lighting of the green screen was really even when you shot it, you won’t have to adjust much of the parameters. You can sometimes get away with just changing the setting to “aggressive.” But, if your green screen was lit less-than-perfect, you will need to adjust some of the parameters.
Premiere Keying: Transparency & Pedestal
There are a few main adjustments that we’ll take a look at. First, if your subject (in white) has some black scattered throughout, adjust the “transparency” slider under “matte generation.” That will clean up your subject to make sure that the hair and small details are included.
Next, to clean up the background (in black) adjust the “pedestal” slider. This will clean up the background and make it completely black in this alpha view. If you have some trouble with the background in the shadows, adjust the “shadow” parameter.
That’s looking pretty good, but we’re not quite done yet. Set your output view back to “composite” so we can see what our video is looking like. Go ahead and put a backdrop behind your subject to give you a better visual reference.
Premiere Keying: Choke & Soften
In most cases, we’ll need to choke and soften the key a bit. Choking the key is the act of “shrinking” in the key. Softening the key is the act of feathering the key out at the edges. Both of these help to create the illusion that your subject is seamlessly in the scene with your background.
Under “matte cleanup,” adjust the “choke” slider up slightly. A little bit goes a long way with choke and soften. Don’t go up too much or it will look weird. I try to never go above 25 with choke.
Adjusting the choke will “shrink” your key.
Next, adjust the “soften” slider until the blending of your subject’s edges look good. Not too much! With “soften” I try to never go above 20.
Adjusting the soften slider will feather the edge of your key.
Adjust both “choke” and “soften” until you have a perfect edge blend.
If you have some green spilling through your subject’s hair, play with the “spill suppression” settings. I sometimes have to bring “luma” and “spill” up a bit when keying difficult clips.
There you go. You’ve just chroma keyed in Premiere Pro!
For bonus points, you can add a drop shadow to your subject to make it seem more natural. NOTE: only add a drop shadow if it makes sense to use with your composited backdrop.
Adding a drop shadow is subtle, but effective.
Chroma keying directly in Premiere Pro will save you time, avoiding having to dynamically link to After Effects. It will also save you render time, which is always good. Depending on your editing system, you might be able to playback the keyed footage in real-time without rendering.
Got Premiere Pro keying questions?
Share your questions and thoughts in the comments below!