Want to get more creative with your videos? Green screen (chroma-key) editing is a standard technique in post-production that let's you layer, or swap out images within a video frame based on color hues (chroma). This is most often used to remove or change the background of a frame (like in a weather newscast) but also can be used to exchange items and add imaginative content to a scene - ideal if you are on a budget or need a little something extra to jazz up your footage.
The opportunity for background creativity and animation in post-production is limitless IF and only if you can properly light, and then key out your green screen footage. So, let's get creative with our green screen editing skills and go through a brief tutorial on how to key out (A.K.A. "keying out" or just "key") green screen using Adobe's After Effects!
Keying Out the Green Screen (Tutorial)
Steps: Adobe After Effects
- Create a new composition in After Effects by dragging your video clip into the 'Composition' icon (you can send any footage you have in CS6 or CC to After Effects via a dynamic link)
- Under 'Effects & Presets' search for the term 'keylight' and apply to your video clip by double clicking it
- Now click the 'Screen Color' eye dropper tool and click on the green screen section of your image
- Now switch the view from 'Final Result' to 'Screen Matte'
- Scroll down to the 'Screen Matte' section and open the menu.
- Tweak the 'Clip Black' and 'Clip White' settings until the background is completely black and the foreground subject is completely white. Keep the 'Clip White' and 'Clip Black' settings as far away from each other as you can without introducing spotting
- Switch the view back to 'Final Result' and you will see a much cleaner key!
- You can also adjust the 'Screen Shrink/Grow' settings which should remove some of the rougher edges.
- Get it right first time: In order for a green screen to be used to it’s maximum potential it should be lit evenly with no wrinkles or dark spots on it. Also your subject should be about 15 feet away from the background to avoid shadows or green spill.
- Keying out the green screen is just as important as lighting your background.