Want to make things flicker in after effects… well there are many way to make that happen. Keyframes, effects, and expressions. This is less of a tutorial and more of a lesson on all the ways you can do the same damn thing in this program. Really there’s no wrong way… unless you’re talking about doing something completely wrong. Actually there is for sure wrong ways to do things.

Anyway, here is the expression we use in here, it’s a doosey…

amp = 50; //MUST BE 50! Governs the height of the wave
freq = 10; //waves per second… kind of.
t=time-marker.nearestKey(time).time; // time based on the marker

x=amp*Math.cos(freq*t*t)+50; // makes the wave

if (time>thisLayer.marker.key(1).time) {100} else {
if (x>50) 100 else 0} // turn the effect on at the marker, and limit the expression

I hope that helps. But if it’s not clear, ask me questions in the comments zone and I’ll try to answer them.

Download this project file:

This project file for this will work in Adobe CS6 and newer (12.2) and WILL NOT work in older versions.