How to Replace Sky in a Video
When filming outside, we all hope for the perfect sky, but we rarely get it. In those situations, motion tracking can save the day (and the sky). In this tutorial, I’ll show you how to replace a disappointing sky in a video with Adobe Stock material.
STEP 1: CREATE A NEW COMP
Open Adobe After Effects CC and create a new composition that’s 1920 X 1080 with a frame rate of 29.97 (or the frame rate of your shot). Rename the file; I called mine “MAIN.”
STEP 2: ROTOSCOPE
Drag your base layer and replacement sky into the new Main Comp. Command (Mac)/Control (Windows)-D to duplicate your base foreground layer.
Take your time to rotoscope out the figure of your subject; the more accurate, the better!
STEP 3: ADD A NEW SKY
Drag your replacement sky layer in-between the two base foreground layers. The Rotoscope layer will be on top of everything.
Use the Opacity [Command (Mac)/Control (Windows)-T] and the color correction Levels to blend the new sky with the original environment.
STEP 4: TRACKING CAMERA
Select the original base foreground layer and select Track Motion. Camera track a solid point—something that will be easy to keep track on.
Create a new Null (Layer > New Layer > Null Object). Go to the Tracker panel, select Edit Target, and select the new Null. Click Apply and make sure Apply dimensions are X AND Y.
Toggle the 3D button on the replacement sky and parent it to the new Null Object.
STEP 5: EXPORT
All that’s left is to export the final piece to the settings you prefer.