Shoot on a green screen

Separate your subject from the background

Scenario:

You are working on a project to shoot a subject, eliminate the background, and insert another background.

It is common to see an actor standing in front of a screen of graphics, or reporters standing in a fake location.

You might put someone into an exotic location. You might place someone over a series of text pages or graphics. You might combine shots of different scales to do a science fiction “Land of the Giants” effect.

The exercise:

Plan a short scene involving live action and existing still or video images.

This can be 30 seconds to 2 minutes.

Green screening is a type of chroma keying, or color-keying. It is similar to using Photoshop's Color Range filter to select a particular color. Video uses a pure and saturated color to make the separation easier. Blue and Green are the most common colors for these effects. Your actor needs to avoid wearing clothing containing the color of your background. You may see a weather reporter wear a tie or scarf that keys out and you'll see the weather map through their chest.

The green screen should be clean, wrinkle-free, and lit evenly. It is best if your actor doesn't cast a shadow on the background.

Do a test before you shoot the real scene. Shoot some video and test the keying with After Effects. The quality of the camera, the backdrop, the lighting, and your software all contribute to success.

This video has some tips for setting up the camera and lights.

Shoot your final scene and combine the two images into a final video.

By the way, why do we use green?

Filmmaker IQ has The History of Greenscreen.

Some tutorials...out of the many you will find:

Greenscreen adjustment in Premiere
https://www.videoschoolonline.com/green-screen-how-to-chroma-key-in-adobe-premiere-pro/

Keying in AE
https://helpx.adobe.com/after-effects/atv/cs6-tutorials/color-keying.html

A 4-part keying series for AE https://www.youtube.com/watch?v=U0x-G8oSue4

Hollywood camera work, free resources: http://www.hollywoodcamerawork.com/greenscreenplates.html