How to Make Something Pulse in After Effects
By Lucas Lalonde
Updated September 28, 2017
Adobe After Effects is a powerful program capable of creating professional video effects that add visual interest to existing video or graphics. While After Effects ships with a variety of plug-ins and pre-coded effects that can create impressive motion graphics presentations, sometimes the user requires more control over an effect. After Effects includes pre-coded "pulse" effects that animate objects such as text, but using those effects allows for less control than building the effect yourself.
Move the play-head to the point on the timeline at which the animation should begin playing.
Select the layer that you wish to animate in the "Layers" palette.
Click the arrow to the left of the layer name to open its layer options, then click the arrow next to "Transform" to open those options.
Drag the "Anchor Point" sliders so that the anchor point cross hair lies directly in the center of the object you will be animating. This ensures that the pulse will originate from the center of the object.
Click the stopwatch icon to the left of the "Scale" attribute to create a key frame.
Press the "Page Down" key five times to move the play-head five frames down the timeline.
Set the horizontal and vertical scale of the layer to 120 percent to simulate the first half of the pulse effect. After Effects automatically creates another key frame.
Press the "Page Down" key three times to move the play-head three frames down the timeline.
Set the horizontal and vertical scale of the layer back to 100 percent, simulating the second half of the pulse effect. After Effects automatically creates another key-frame.
Drag a selection box around the three key-frames in the timeline and press "F9" to activate "Easy Ease," smoothing the animation between the frames.
Press "Shift+Page Down" to move 10 frames down the timeline. Press "Ctrl+C" to copy the animation frames then press "Ctrl+V" to paste the animation at the frame where the play-head sits.
Continue moving down the timeline 10 frames and pasting the effect at each interval to simulate the pulse effect as many times as desired.
Try playing with the scale settings to alter the size of the pulse effect. You may also want to increase or decrease the number of frames between each key-frame to achieve a quicker or slower pulse.
Lucas Lalonde has been a freelance writer since 2007. His topics of expertise include nutrition, weightlifting, graphic design and Internet marketing. His work has appeared online and in south Louisiana newspapers, including the "Teche News" and the "Vermilion." Lalonde holds a bachelor's degree in English from the University of Louisiana at Lafayette.