The main purpose for shooting on a greenscreen is to be able to remove the color and have a transparent background. Make sure when lighting your background, the lighting is as even as possible.
Tutorial
Here are the steps in After Effects that I follow when pulling a greenscreen key:
Add color key
Grab green by person
Adjust tolerance
Add another color key
Grab green (with eye dropper) near the edge (that is not being keyed)
Adjust tolerance
Add simple choker
Expand the matte to like -100…
Create new magenta solid
Add “Keylight”
Select a green color
Change view to “combined matte”
Under screen matte
Raise the “clip black” just a little
Lower the “clip white” just a little
Make sure not to lose the fine detail
Use screen shrink/grow to bring it down to like -1.5 or so…just to get rid of any little green spill
Change screen softness to 2 or so…
Change soft color to hard color (personal taste)
Conclusion
There are many programs that will allow you to pull out a key based on chroma (color), but After Effects is an industry-standard tool. Hopefully, you find this tutorial helpful.
Happy keying!
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