Picture Gandalf looking over the valley of Rivendell. Or Gatsby riding down the street in the 1920s. Or massive, earth-shattering explosions lighting the sky behind the Avengers. The magic of movies means that the audience doesn’t stop to wonder how the scenes were created. We are there with the characters in these fanciful, faraway locations, never pausing to wonder how blockbuster movies can defy the laws of physics.

Developed by RKO Radio Pictures, early green screen films included Flying Down to Rio (1933) and The Thief of Bagdad (1940). Today, green screens are a part of almost every major motion picture. According to filmmaker Zach Lipovsky, “Green screening is just basically telling the camera to replace anything it sees as green when whatever you [the director] want.”

Here’s an example from an entry in MobileMovieMaking’s 2016 Halloween contest:

But how can you, an independent filmmaker, bring the green screen to your productions? Green Screen Made Easy (the 2nd edition) has your answer. This updated guide outlines the basics of shooting, assisting actors, and techniques to provide you with the help you need to produce a fantastical film.

Co-authors Jeremy Hanke and Michele Yamazaki Terpstra begin by defining “chroma keying,” the scientific phrase for “green screening.” Jeremy and Michele say, “Chroma keying is simply removing any color that you designate and creating a matte in the shape of the removed color.”

Defining is the first step toward understanding. The next step is to set up your actual green screen. There are many different options when deciding on the type of screen (including whether the screen will actually be green; blue is another acceptable choice). Green screens can be purchased or, if you are adventurous, built from scratch. However, Hanke and Terpstra state, “There are often distinct advantages to going with professional supplies.”

The authors provide camera tips and production ideas to get the most out of your green screen shooting. This includes helping actors to perform best while pretending to be somewhere they aren’t.

Once you’ve mastered the production details, you can continue on to the actual art of keying, where you will learn techniques that “will give you killer results.” This chapter is where the real green screening starts. You’ll learn how to use “core mattes and edge mattes to isolate areas” and how to fix “holes with hold-out matters,” along with other smaller issues you’re likely to encounter on your green screen journey.

So whether you’re movie is set on Earth or Mars or some distant planet yet to be discovered—whether you’re filming underwater chase scenes or viewing the Paris skyline at night (while filming in Cleveland), green screening is sure to fill your movie with all the colors of the rainbow.