8. Hide the Lumetri Color options in the Effect Controls panel.
9. Choose File > Save to save your work.Replacing the background
These shots were taken on a clear day with few clouds. To add a little drama, you’ll key out the
sky and replace it with storm clouds. You’ll start by using the rigid mask tracker to mask the sky,
and then key out the sky color. Then you’ll replace it with another image.
Using the mask tracker
The mask tracker transforms a mask so that it follows the motion of an object or objects in a
movie. It’s similar to the face tracker you used in the Extra Credit project in Lesson 9. You can
use it to mask a moving object so that you can apply a special effect to it, for example. In this
case, you’ll use it to track the sky as it shifts in a handheld camera. There is a great deal of blue
in this clip—in shadows, the cape, and other areas—so it would be difficult to key out the sky
without first isolating it.
1. Go to 2:22—the last frame in the first clip before the transition begins.
2. Select the Close Shot layer in the Timeline panel. Then select the Pen tool ( ) from the
Tools panel.
3. In the Composition panel, draw a mask that follows the roofline of the buildings. Complete
the mask outside the image in the Composition panel, as shown below. It’s okay if the mask
cuts off the boy’s head, because his head doesn’t contain blue and won’t be keyed out.