After Effects CS3 inventing keyframes HELP!

[Todd Kopriva]

There’s additional information about this behavior (which some people refer to as “boomerang motion”) in the “Controlling change with interpolation” section of After Effects Help. That page gives solutions in addition to the ones that Dave outlined, and it points to some tutorials back here on the COW by Aharon Rabinowitz, in which he explains everything very well.

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Todd Kopriva, Adobe Systems Incorporated
putting the ‘T’ back in ‘RTFM’ : After Effects Help on the Web
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[Justin Brinkmeyer]

Thanks a lot. What I am experiencing isn’t exactly what you described but I’m sure they are related. I will check out your links, try what you said tomorrow and post back.

Thanks again for the quick reply!

[Justin Brinkmeyer]

Thanks for the response. My situation is a little different than you described. The goofiness is happening between 2 key frames in which there is a change in value. The animation starts correctly and finishes correctly but even though it is a linear movement, it is doing it own swooping and scaling in between, just making up its own movement. This is entirely frustrating and nonsensical.

It is just a position movement (with rectangular mask movement as well) on the X axis. For some reason around the middle of the 2 key frames it drops on the Y axis.

[Brian Charles]

What shows up in the graph editor?

[Justin Brinkmeyer]

In the graph editor there is a nice straight line in between the two keyframes, yet it deviates from the y-axis (in the animation not the graph)

[Jason Pope]

I am also having this exact problem.
It is the ‘boomerang’ effect, but changing the keyframe interpolation to linear or hold does nothing – After Effects still creates a boomerang motion between keyframes for no reason.

I have a still graphic and I am animating scale and position simultaneously – scaling up and moving position in a straight line. When I play the animation the movement is a crazy swooping, regardless of what I

Does anyone else have this problem or a solution?
Any help would be greatly appreciated.

[Bradinn French]

I was having this same problem and ran into this thread. In my case it was usually position keyframes which would move back and forth to get from 1 keyframe to the next. So if I set one keyframe at 0.0 and the next at 30.0, it might dip to -10.0 inbetween them and then go back out to 30 by the 2nd keyframe. Or even stranger, I would have 2 keyframes with identical XYZ positions, but they would slightly move inbetween only to return once I hit the 2nd keyframe.

The solution I found was to right click on the 2nd keyframe (where there is unwanted motion between the 1st and 2nd) and select Keyframe Interpolation. In the Keyframe Interpolation window, you should change the value in the Spatial Interpolation dropdown to LINEAR if it is set on Bezier or Continuous Bezier. I found in all instances of this happening for me, the Spatial Interpolation was either set on Bezier or Continuous Bezier. This does not appear to affect the Easy Ease settings (at least for position keyframes) which are set by the Roving dropdown.

[Johnathan Throbins]

Something that might help:
When you scale and move position, remember where your anchor point is. The scaling and position change often end up at odds if the anchor point is not in the middle of your motion path and you’re scaling quickly. This can be circumvented by parenting with null objects whose anchor point is nearer /at one of the action points /on screen at least. You can add a new null in a chain of nulls for each movement. It’s kind of a pain, and maybe someone else has a better way, but I’ve found this helpful especially when I want to use expressions to determine rate of change or bezier curves on position while scaling etc…

Just figured I’d add one more solution to the list here for the next passer by.