A perfectly shot green screen is very difficult.
Most of the time, getting a good key from a green screen is more complicated than just choosing a color to key and it all just magically works.
That could be ok for quick and dirty composites, but when you want feature-film-quality work, you may need to do a few passes.
The idea is to create multiple mattes from keying different parts of the subject, that you then combine to create the perfect key.
It’s a smart way to work, and saves you from fiddling forever trying to make just one key work.
In this video from Casey Faris, you’ll learn about:
- Keying with the Delta Keyer
- Refining the matte
- Viewing over a temporary background
- Doing another key with 2nd Delta Keyer
- Using a Matte Control node to combine mattes
- Using a mask to control where the 2nd key is applied
- Example of several combined keys.

Gedaly is the Founder and Lead Educator of DVResolve.com and is Blackmagic Design Certified Master Trainer. He’s edited commercials for major brands and has done color & VFX for independent films. He consults on post-production workflow and creating online education. Gedaly is the co-founder of Working.Actor, a former marketing manager for large brands, and creates original film projects with his production company Razee.