How to Edit Green Screen Footage in Final Cut Pro X

Final Cut Pro December 13, 2019 8 min read

Using green screen clips in Final Cut Pro is a great way to transport your video production anywhere in the world—without having to blow your budget on expensive plane tickets. It’s also great for compositing footage onto phone screens, simulating movement when a car is still, or anything else you can think of! 

This tutorial will take you through the basics of green screening using Final Cut Pro’s Chroma Key effect, along with pro tips for shooting quality green screen footage. Let’s dive in!

Part 1: How to Edit Perfect Green Screens in Final Cut Pro

If your green screen footage was shot correctly, you’ll be amazed how quick and easy it is to instantly remove the green screen using Final Cut Pro’s automatic Keyer effect. If you want to follow along with this tutorial, download one of Motion Array’s green screen stock footage clips

Step 1: Add Keyer Effect to Your Footage

Final Cut Pro’s Keyer effect is a built-in feature for removing green or blue backgrounds from your clips and making them transparent. 

  1. If you haven’t already, create your project in Final Cut Pro and import your footage. 
  2. Add your footage to the timeline.
  3. Open the Effects Browser and find the Keyer effect. Drag this to your clip in the timeline to add the effect. 

Step 2: Sample a Color Range to be Keyed

Chroma Key works by making parts of your image transparent, based on their color. Final Cut Pro may have automatically detected the appropriate color range when you added the effect, but if it hasn’t you can help define the color range using the Sample Color adjustment.

  1. Move the Playhead to a time in your footage when the greenest background is visible. 
  2. In the Keyer controls inside the Video Inspector, select Sample Color.
  3. Draw a rectangle anywhere where you can still see green showing through your background. This will add that color range to your Color Selection and should make that area transparent.

Step 3: Refining Edges

Sometimes the automatic keying has trouble determining the exact boundaries of your green screen. This is especially common when there is a color spill, causing some visible green highlights on your subject.  

  1. In the Video Inspector under the Keyer controls, choose the Edges control.
  2. Delineate edges in the Viewer by clicking and dragging your mouse. 
  3. To adjust an edge, move the blue circles and the line in the middle. The further apart the blue circles, the softer the edge will appear in your video. 
  4. Repeat this process until you’ve fixed all the edges in your video. 
  5. Move the playhead around in your clip. If the subject moves about, you may need to adjust the edges multiple times throughout the clip. 

Step 4: Compositing Your Background and Foreground

After adding the Keyer effect, you should immediately see the green portion of your footage disappear. By placing an image behind your footage, you can composite the two together. 

  1. Add your background image to the Timeline below your green screen clip. 
  2. Using the Transform controls such as Scale and Position, adjust the background image, so it is framed appropriately.
  3. You can adjust either the background image or the foreground subject with the keyer effect. Either can be controlled by selecting it in the Timeline and adjusting its controls in the Inspector.

With most high-quality green screen stock footage, these steps should do the trick of making your green screen effect look top-notch! The best green screens have consistent luminescence, no color spill, and light the subject independently.

Part 2: Adjustment Controls in the Keyer

Keyer Controls

So let’s say you wanted even more control over your effect, the Keyer comes with an entire panel of parameters which can come in useful if you’re working with imperfect green screen footage. They can all be found in the Inspector.

Strength

This slider narrows the range of colors identified by the keyer. The default is 100%, but you can decrease this if you’re losing too much of your image to transparency. 

Jump to Sample

Clicking the left and right arrows next to Jump to Sample will bring you forward or backward to the next color sample. If conditions in your footage change over the course of your clip, you can make multiple samples and adjust them independently using all of the Chroma Key.

View

View gives you three options for previewing your chroma key effect, allowing you to see a Composite of the foreground and background, Matte which shows transparent areas as black and foreground areas as white, and Original allows you to see the image without the effect.

Fill Holes

Increasing this slider does what you’d expect, if there are any unwanted holes inside your subject after using the Keyer, you can crank this up to fill them in. 

Edge Distance

Edge Distance works together with Fill Holes to determine how far into the interior of your subject a “hole” must be before it gets filled. If you increase this too much you can create unwanted translucency near the edges. 

Spill

If some of your background color is spilling onto your subject you can adjust the Spill level control to remove it. This often happens if your scene was lit improperly allowing light to reflect off the background onto the subject. 

Invert

Invert will swap your key matte, making your keyed background opaque and your subject transparent. This is useful for removing everything outside of a certain color range (instead of inside a color range).

Color Correction

Color Selection

Expanding this panel (by clicking the small triangle to the left) will open up controls for adjusting the color range used by the Keyer to apply transparency to your footage. 

If Scrub Boxes is selected, your adjustments will only be made to the transparency of your edges, and the Sample Color you selected in the above Refine Key parameter will be maintained. If Manual is selected, you can take total control and adjust both the edges and the core transparency settings. 

You can drag and adjust the Chroma (hue) range as well as Luma (brightness) by dragging them with your mouse. If Manual is selected, you will be able to adjust both the edge range and core transparency ranges here.

The Chroma Rolloff and Luma Rolloff controls adjust the S curve of their respective parameters which is the steepness of falloff transparency around the edges of your subject. 

Fix Video is on by default, and will automatically smooth out jagged edges. If you find that the quality of your key has been degraded, you can try toggling this option off. 

Matte Tools 

Matte Tools

Switching to the View parameter above to Matte will allow you to view how the Keyer divides your image into transparent, translucent, and opaque areas. The Matte Tools parameters adjust this matte. 

Levels adjust the contrast of your matte. You can drag the black, white and grey sliders to adjust the Keyer’s ranges for transparency, opaqueness, and translucency.

Drag the Shrink/Expand slider to the left to make translucent regions of your matte more transparent or drag it right to make them more solid. 

Using the Soften control will feather the edges of your matte, it is useful if your matte has some imperfections around the edges that you would like blurred. 

Erode is used to shrink your matte inward, increasing transparency at the edges. 

Spill Suppression

Spill Suppression

If you have unwanted spillage of your background color onto your subjects, you can use Spill Suppression to try to remove it. 

Spill Contrast adjusting this can get rid of the grey outline that sometimes surrounds a subject after using spill suppression. 

Tint controls the amount of complementary color (magenta for green and orange for blue) that is added to your image to make up for the spill suppression.

Saturation controls the range of colors affected by the Tilt slider. 

Light Wrap

Light Wrap

By mixing highlights from your background with your foreground subject’s edges the Light Wrap feature can make it appear as if light from your background is wrapping around your foreground object. 

Amount adjusts the total amount of the light wrap effect.

Intensity increases the brightness of the light.

Opacity can be adjusted to increase the opacity of your subject. 

Mode includes 5 options that you can try to achieve the best effect. The 5 options are Normal, Lighten, Screen, Overlay, & Hard Light.

Part 3: Other Editing Tricks for Green Screen Videos

Color Correction

If your subject and background were shot under different lighting conditions, they might look a little bit off when composited together with a green screen. This can be easily fixed with Final Cut Pro’s one-touch “Color Match” function.

  1. Choose the clip you’d like to adjust (usually the one which takes the least amount of screen space), and select Modify > Match Color on the top menu bar. 
  2. Drag your mouse across the other clip to find a suitable point, and then press Apply Match
  3. The color of your foreground and background images should match. If you want to make even more adjustments, you can use the Color Inspector

Masking

When transporting your subject to another location using a green screen, you only need to isolate their immediate surrounding area. If other parts of the shot don’t have perfect green screening, those can be ignored with a mask. 

  1. Open the Effects Browser and select Draw Mask. 
  2. Drag the effect onto your green screen clip.
  3. “Click to Add a Control Point” should appear in the Viewer. Use the Pen tool to draw a mask around your subject. This does not need to be super detailed, just enough to surround include your subject and exclude any unwanted areas. When you’re finished, everything outside the mask should disappear. 
  4. Play through your video and make sure the subject stays within the mask the entire time. If they don’t, you can make adjustments to any of the control points. 

Part 4: Shooting Great Green Screen Footage

If you’re shooting your own green screen footage, setting things up correctly can save you a lot of time during post-production. These pro tips should cover everything you need to know about capturing high-quality green screen footage on your camera. 

1. Background

When shooting green screens, the goal is for your background to be uniformly colored and lit, which will make your job of keying much easier during post-production.

As a rule, a painted flat background is the best, and the next best is fabric stretched out with no wrinkles. The area directly surrounding your subject is the most important, as other parts of your frame can be removed with a mask. 

Finally, make sure there is no green present in your foreground subjects’ clothing, or you will have to spend extra time removing that in post-production.

2. Lighting

The key to lighting green screen footage is to light the background and foreground separately and try to achieve uniform luminescence across your background without any highlights. Make sure your subject is not casting any shadows against the green screen, which generally means your backdrop lights will need to be behind the subject and off to the sides.

For lighting the subject, try to use standard three-point lighting with a backlight, key light, and fill light—but you’ll need to make sure none of your lights are spilling onto your green screen. To do this, you may need to raise your lights and point them downward, or use black flags to block any interference with your backdrop lights.

As a final tip, consider adding a magenta filter to your backlight, which will minimize the amount of green bleeding around your subject and make keying the edges easier. 

3. Camera Settings

In addition to setting up your studio correctly, there are a few camera settings that can really improve your green screen footage. If your subject will be making fast movements, motion blur can make keying them difficult. Try setting a high shutter speed like 1/80 or 1/100, which should help reduce motion blur in your footage.

Another simple trick is to use a narrow depth of field, so your background is blurry. Try recording with an open aperture like f4 to reduce visible details in your background. 

Before capturing your own footage, make sure to check out what’s available online for green screen footage


That covers just about everything you need to know for editing realistic green screen videos in Final Cut Pro. Once you’ve mastered the Keyer tool and made sure that you’re capturing high-quality green screen footage in the first place–you should be able to produce realistic-looking productions set anywhere in the world!