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LESSON 15 Exploring Compositing Techniques
Getting started
Adobe Premiere Pro and other Timeline-based, multitrack nonlinear editors have a 
general operating practice: Clips placed in higher video tracks cover up whatever is 
below them. However, the object isn’t to use clips in these higher tracks to obliter-
ate what’s beneath them. It’s to combine the content from the various tracks using 
a technique called 
compositing
.
In fact, you’ve already used compositing, back in Chapter 7, when you inserted a 
title over your video. As you’ll learn in this chapter, Adobe Premiere Pro gives you 
many ways to composite videos, graphics, and images for best effect.
You use compositing techniques on clips so the clips below them on the Timeline 
can show through. The five basic compositing methods are as follows:
t
Reducing the opacity of an entire clip
t
Combining layers based on a blend mode
t
Using alpha-channel transparencies in clips and effects
t
Color keying a green-screen shot
t
Using matte keying effects
In this lesson, you will try all of these compositing methods and use different tech-
niques with a few you’ve already tried. Once you see all the possibilities, you’ll start 
to plan and shoot your projects with layered videos, graphics, and images in mind.
Making compositing part of your projects
You see compositing when you watch a TV meteorologist standing in front of a 
map or some other graphic background. As shown in the photos here, most times 
the person is standing in front of a green or blue wall. The technical director uses 
a
keying
effect to make that wall transparent and then inserts a weather graphic. 
You can do the same thing in your video projects by using an Adobe Premiere Pro 
video keying effect.
Matt Zaffino, chief meteorologist—KGW-TV, Portland, Oregon

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Many movies, as well as most computer games with live actors, use compositing. 
Green-screen
studios enable game developers and film directors to place actors 
in science fiction and other artificial settings created with 3D computer graphics. 
Such sets make it possible for actors to work in relative safety while the finished 
product shows them dangling from a skyscraper, hundreds of feet in the air.