The easiest way to change rotation speed in After Effects is by adjusting the keyframes on your rotation property. You can increase the speed by spreading the keyframes further apart or decrease the speed by bringing them closer together.
Here's a more detailed breakdown:
Keyframe Manipulation
- Locate the Rotation Property: In your Timeline panel, open the layer you want to rotate, then open the "Transform" properties. You'll find the "Rotation" property there.
- View Keyframes: If you've already set keyframes for the rotation, you'll see them along the timeline next to the Rotation property. If not, click the stopwatch icon to enable keyframing and set your starting and ending rotation values.
- Adjust Keyframe Spacing:
- Increase Speed: Select one of the rotation keyframes and drag it further away from the other keyframe(s). The rotation will now happen in a shorter amount of time, thus increasing the speed.
- Decrease Speed: Select one of the rotation keyframes and drag it closer to the other keyframe(s). This stretches the rotation over a longer period, decreasing the speed.
Example:
Imagine you have two keyframes: one at 0 seconds with a rotation of 0 degrees, and another at 1 second with a rotation of 360 degrees. This creates one full rotation in one second.
- To increase the speed: Move the second keyframe to 0.5 seconds. Now, the rotation happens in half a second, making it twice as fast.
- To decrease the speed: Move the second keyframe to 2 seconds. The rotation now takes two seconds, making it half as fast.
Additional Tips:
- Graph Editor: For more precise control, use the Graph Editor (click the Graph Editor button above the Timeline panel). This lets you adjust the rate of speed change (easing) between keyframes. You can create smoother or more abrupt changes in rotation speed.
- Expressions: For more complex or automated rotation, use expressions. For example, you could link the rotation to a slider control or a time-based calculation. This allows for dynamic rotation based on other parameters. A simple example would be
time * 100;which would rotate the layer 100 degrees per second.
By manipulating keyframes, you gain complete control over the rotation speed of your layers in After Effects.
