Green screen

This is a mix of editing techniques and technology, that is used to superimpose your subjects onto virtual backgrounds, place them over animated backgrounds, or transport them to any location that you may want.

It is a process called keying. This is where you isolate a single color or brightness value in an electronic image and using software to make that value transparent, allowing another image to show through the affected areas.

Any color can be keyed, but green is most commonly used as the subject is unlikely to wear green, opposed to a blue screen where people are more likely to wear blue clothing. 

How it works

First you need to buy a green (or other color) screen. These can be relatively cheap.

You need to make sure that the lighting is smooth and from different angles to make sure that there are no weird shadows. Also make sure that there are no creases in the screen, as if there is any it will make the new background have creases in and will make it look odd.

Next you should import the footage into your timeline, on whatever editing software that you use. Then apply a chromakey filter onto the footage, this will offer you adjustment options in the effects control panel. Your footage should be at a 4:2:2 ratio as it is much easier to key than 4:2:0, so make sure that the settings on the camera is correct.

I could use green screens if I need to film anything and have it in a different location that I would not be able to get to in person.