Laurie Knapp returns with a look at using Nulls in After eFfects as controls for animation, and adds a bit of expressions to simplify some things.

“Using nulls as the control mechanism for your camera or object paths is a simple and yet often overlooked technique. Think of a null object as a camera rig. You can attach everything you need to it and move it all at once…and the movement is a lot smoother and more flexible.”

Here I demonstrate a simple expression to tie the emitter position of a particle light-streak to a null motion path, which makes animating my particle path over some aerial mountain footage a lot easier!

The mountain footage comes from the VideoBlocks stock collection at:
videoblocks.com/?videos/?details/?terrain/?

With the free 7 day trial, you can download this footage (and more!) and work along with this tutorial if you are unfamiliar with using nulls, writing expressions, or creating particle streaks.