How to Chroma Key in DaVinci Resolve

Chroma keying makes a selected screen color transparent so another image or video can show behind your subject. The cleanest results start with an evenly lit green or blue screen, a subject separated from it, and footage recorded without excessive motion blur. Resolve’s menus and panel layouts can differ slightly by version; the steps below use the Fusion page and its Delta Keyer.

What You’ll Need

DaVinci Resolve and a video clip with a green or blue screen.
A background image or video, or a solid-color background for a basic test.
A computer able to play your footage smoothly; proxy or optimized media can help with demanding clips.

Step-by-Step

Start a project and import media. Create or open a project, then import the screened clip and the background using the Media page or the Media Pool. If Resolve asks to change the project frame rate to match the clip, choose the option that fits your intended delivery.
Layer the subject over the background. On the Edit page, place the background on Video Track 1 and the green-screen clip on Video Track 2, with both clips aligned in time. The upper track should contain the subject; the lower track will show through the transparent area.
Open the clip in Fusion. Select the foreground clip and click the Fusion page. The node graph normally shows a MediaIn node feeding a MediaOut node. If the node graph is unfamiliar, keep the original MediaIn and MediaOut nodes and add the keyer between them.
Add a Delta Keyer. Select the connection between MediaIn and MediaOut, then add a Delta Keyer from the Effects Library. You can also search for “Delta Keyer” in the library. Confirm that the image flows from MediaIn through the keyer to MediaOut; connecting the nodes incorrectly can leave the viewer blank.
Choose the screen color. Select the Delta Keyer node. In its controls, use the background-color eyedropper and click a representative area of the green or blue screen in the viewer. Sample a clean, evenly lit section rather than a shadow, bright reflection, or area touching the subject. The screen should become transparent, revealing the background when you return to the Edit page.
Inspect the matte. Use the keyer’s matte or alpha preview controls to see what is opaque and transparent. The subject should be solid, while the screen should be black or transparent in the matte view. Adjust the keyer’s controls gradually to remove leftover screen without cutting into hair, clothing, or other fine detail. Control names and available options may vary by Resolve version.
Refine edges and remove spill. Use the keyer’s edge, matte-cleanup, and despill controls where needed. Increase cleanup only enough to remove holes or specks; too much can make edges harsh or erase fine detail. Despill reduces green or blue color reflected onto the subject, but overdoing it can make skin, fabric, or other colors look unnatural.
Check the composite and render a test. Return to the Edit page and review the result over the actual background. Check the entire clip, especially movement, hair, transparent objects, and the subject’s outline. Adjust the foreground’s size and position if needed, then render a short section on the Deliver page and inspect the exported file before rendering the full project.

Common Mistakes

Using uneven lighting: A single color sample may not remove a screen with bright patches and deep shadows. Improve the lighting or adjust the key carefully for the variations.
Sampling the wrong area: Avoid sampling near the subject, a shadow, or a reflection. These can introduce unwanted colors into the selection or make the key inconsistent.
Over-cleaning the matte: Aggressive cleanup can remove hair, soften the subject, or create a visible cutout edge. Compare the result with the original and back off if detail disappears.
Forgetting track order: The foreground belongs above the background in the Edit timeline. If the background covers the subject, check the track arrangement and Fusion output.
Ignoring spill and edge color: A transparent screen does not automatically remove colored light reflected on the subject. Use restrained despill and inspect against the final background.
Judging only on one background: A matte can look acceptable over black but show obvious fringes over a bright image. Review it over the background you plan to use and, if useful, a contrasting temporary color.

Tips

When recording, keep the subject far enough from the screen to reduce colored spill and shadows. Light the subject and screen separately when possible.
Avoid clothing or props that match the screen color; the keyer may make those areas transparent too.
Use the original full-quality media for the final render if you edited with proxies, and confirm the correct media is linked.
Keep a copy of the original clip and make small, reversible adjustments. A clean source generally matters more than extreme keyer settings.
For a moving camera or uneven screen, consider whether the shot needs additional masking or tracking. A key alone may not remove areas outside the screen cleanly.

Troubleshooting

The screen remains visible: Check that the Delta Keyer is in the image path and that you sampled the correct screen color. Try a clean sample, then inspect the matte and make modest adjustments to the key range or cleanup controls.
Parts of the subject disappear: The sample may include a color present in the subject, or the key may be too broad. Undo the last adjustment, choose a cleaner screen sample, and reduce the strength of the change. Re-shooting with different wardrobe may be necessary if subject colors match the screen.
The edges look jagged or noisy: Check focus, motion blur, compression, and lighting in the source. Use the keyer’s edge or matte controls gently; excessive smoothing can make fine details look soft.
A colored outline remains: Adjust despill carefully and check the subject against the final background. If the outline is part of the screen spill or shadow, improve the matte or mask the affected area rather than pushing despill until the subject’s colors change.
The viewer is black or the background is missing: Confirm that MediaIn feeds the keyer and the keyer feeds MediaOut. On the Edit page, confirm the background is on a lower video track and overlaps the foreground clip in time.
Playback is choppy: This may be a performance issue rather than a keying error. Lower viewer playback resolution or use proxy/optimized media if available, then judge final quality from a rendered test.

Frequently Asked Questions

Can I chroma key in the free version of DaVinci Resolve?

DaVinci Resolve includes Fusion tools for compositing, including the Delta Keyer. Availability and interface details can vary by version, so check the installed version’s tool list if you cannot find it.

Should I use a green screen or a blue screen?

Use the color that contrasts most with the subject. Green is common, but blue can be a better choice when the subject contains green; avoid having clothing or objects match the chosen screen.

Can I key a poorly lit green screen?

Often, but uneven lighting, shadows, and wrinkles make a clean matte harder to achieve. Correct the lighting in the source where possible, then refine the key without removing subject detail.

Why does the background not appear after keying?

Make sure the background clip is on a lower video track, overlaps the foreground in time, and is not hidden or disabled. Also verify the Fusion node flow reaches MediaOut.

Can I use the same key settings for every clip?

Not reliably. Screen color, lighting, camera exposure, and subject movement vary by shot. Treat the settings as a starting point and inspect each clip’s matte and edges.

Sources: Blackmagic Design Support. Menus and buttons can differ slightly by version. Spotted something out of date? Tell us.