You’ve dropped a green screen clip on your timeline and now you’re staring at a wall of green that needs to disappear. Premiere Pro handles this natively with Ultra Key — no plugins, no round-trip to After Effects. Here’s the full workflow, including the matte-checking step most tutorials skip.
Apply Ultra Key and Sample the Green
Find Ultra Key in the Effects panel under Video Effects → Keying, and drag it onto your clip. In the Effect Controls panel, grab the Key Color eyedropper and click a green area of the frame — ideally close to your subject, since that’s where the key needs to be most accurate. Uneven lighting means the green near your subject and the green in a far corner are different colors; sample the one that matters.
Most of the green should vanish immediately. The Setting dropdown offers Default, Relaxed, and Aggressive presets — Aggressive pulls a harder key for unevenly lit screens, at the cost of eating fine edge detail. Start with Default and only escalate if the key doesn’t hold.
Check the Matte, Not the Picture
This is the step that separates a passable key from a clean one. Switch the Output dropdown from Composite to Alpha Channel. You’ll see the matte in grayscale: your subject should be solid white, the background solid black.
Gray areas are the problem. Gray in the background means leftover semi-transparent green haze; gray inside your subject means parts of them are going transparent. You can’t reliably spot either issue in the composite view — a slightly transparent shirt looks fine until you put footage behind it.
Clean Up the Matte
With Alpha Channel view still on, work through the Matte Generation controls: Transparency, Highlight, Shadow, Tolerance, and Pedestal. Raise Pedestal to crush noisy gray specks in the background toward black; adjust Shadow and Highlight to fill gray holes in the subject.
Then move to Matte Cleanup. Choke shrinks the matte inward — useful for eating a thin green fringe, but keep it low. Values beyond 20–30 start deleting hair and soft edges. Soften blurs the matte edge slightly, which helps the subject sit into the background instead of looking cut out with scissors.
Switch Output back to Composite and check the result against real background footage, not just black.
Remove Green Spill
Even with a perfect matte, green light bounces off the screen onto your subject — green edges on hair, a green tint on shoulders. Ultra Key includes a built-in Spill Suppression section that desaturates and neutralizes the contaminated colors. Push the Spill value up until the green cast disappears, but stop before skin tones shift; spill suppression works by removing green, and faces contain more green than you’d expect.
If the footage is compressed or badly lit and the key still looks blotchy after all this, the fix usually isn’t more Ultra Key tweaking — it’s a different toolset. See how to fix faulty green screen footage for the Key Cleaner and Advanced Spill Suppressor workflow.
Practice on Pre-Keyed Overlays
You don’t need to shoot anything to practice keying. Pre-keyed green screen assets — effects rendered on a pure, evenly lit green background — key perfectly on the first eyedropper click because there’s no lighting variance to fight. Grab a free green screen hearts overlay or a falling snow overlay, drop it on a track above your footage, apply Ultra Key, and you have a finished composite in under a minute.
That’s also the fastest way to add effects to real projects — there are five common ways to use green screen overlays that never require a physical green screen. And for overlays rendered on black instead of green, skip keying entirely and use a Screen or Add blend mode.
Quick Reference
- Effects → Video Effects → Keying → Ultra Key, drag onto clip
- Key Color eyedropper → sample green near the subject
- Output → Alpha Channel → fix gray areas with Matte Generation
- Choke and Soften (small values) in Matte Cleanup
- Spill Suppression to remove green bounce
- Output → Composite → check against real background footage
FAQ
Do I need a plugin to key green screen in Premiere Pro?
No. Ultra Key ships with every version of Premiere Pro and handles well-shot green screen footage cleanly. Third-party keyers only earn their price on difficult footage — heavy compression, motion blur, or badly lit screens.
Why does my key look blotchy or noisy?
Usually compression. Most cameras and phones record 4:2:0 chroma subsampled footage, which stores color at a fraction of the image resolution — exactly the data a keyer depends on. Uneven screen lighting makes it worse. Check the Alpha Channel view, raise Pedestal, and if it still chatters, use the Key Cleaner workflow in After Effects.
Should I use Ultra Key or Color Key?
Ultra Key. It’s a full chroma keyer with matte cleanup and spill suppression built in. Color Key is a simpler effect that removes a single color value with basic tolerance — fine for flat graphics, not for footage of people.
How do I get rid of the green edge around my subject?
Two tools, in order: a small amount of Choke in Matte Cleanup to shrink the matte past the fringe, then Spill Suppression to neutralize green light reflected onto the subject. If you find yourself choking hard enough to eat hair detail, the problem is spill, not the matte.
