Green screen (or chroma key) filming has been popular in schools for a number of years. It uses software or an app to combine different images or video so that one appears as if part of the other. The green screen effect uses the chroma key feature of the software, so that a person or object standing in front of a green screen will appear in the video with the green screen replaced by another chosen background image or video. To produce green screen in the classroom you will need:
- A green background – you can use a cloth or cover a wall with paper.
- A camera and computer or you can use a tablet or even a smart phone.
- An app or program that supports chroma key.
Ideas for using green screen in the classroom include news reports from exotic locations, weather reports, learning the names of the planets by visiting them and tours of historic locations including travelling back in time.
Green Screen Tips
Make sure your screen is held tight – you don’t want creases in the fabric.
A tripod will help deal with shaky hands and will make the process much easier.
Subjects should not wear any green clothing as that will disappear in the film.
It is worth using external lighting projecting on the screen and not the subject.
Avoid shadows on the green screen – aim for an even colour.
Subjects shouldn’t be too close to the screen – aim for around 60cm.
Check the viewfinder to ensure that the subject is within the green screen and be careful not to film beyond the green area.
If you have more than one subject moving, avoid them crossing each other paths.
Recommended hardware and software for Green Screen
Background: A green table cloth or sheet attached to a wall or frame. Available to purchase for a few pounds. You can also paint or attach large green sheets of paper to a wall.
Hardware: A webcam or video camera connected to laptop or desktop computer. Alternatively a tablet (or mobile phone).
A tripod is highly recommended and additional lighting will help you avoid shadows.
Software: Most video editing software has a chroma key function or you can use a dedicated app. Most of the apps/programs below are inexpensive and some are free.
Windows: I Can Present
iPad tablet: DoInk
Android tablet: Kinemaster