Color Key in After Effects
Using After Effects you can isolate and remove a single color from your composition.
This is relevant when using a green screen, or experimenting with possible effects.
You should have After Effects open, a composition made,
and your footage placed into the composition.
If you look to the very right of the application window, you will
see a dropdown that reads “Effects and Presets.”
A ways down you will see “Keying.”
Under keying there is a list of
possible effects.
Feel free to experiment with as many
as you can. For the most basic
and effective keying, the best option
is often “Linear Color Key.”
Drag this directly onto the clip in your
composition.
Look to your Project window.
You’ll now see that it toggles
between Project window
and Effects Controls.
The Linear Color Key should be
there. Use the small eyedropper
to select the color to key out.
Or open the color selector and choose it.
Play with the parameters of the color key.
Matching Tolerance will adjust how much of your
selected color the effect will remove.
See what changing these does to your image.
Another effect worth knowing about is “Key Cleaner.” Find it in the same drop down as Linear Color
Key. The Key Cleaner can smooth the edges of your keyed area. Also, don’t be afraid to use sever-
al keying effects at once. With balanced lighting on your background After Effects should be able to
remove a great deal of your selected color. But you might want to experiment with what the effect
gives you. Bring in the footage you intend to set behind the subject and make adjustments. Color
keying can be an interesting effect even without use of a green screen. Remove all one color and
see what happens.
DARTMOUTH COLLEGE
FILM AND MEDIA STUDIES TECHNICAL SUPPORT
Adobe After Effects
