Reply To: Does animation on twos or ones even matter in 3d animation?

[Wayne Dixon]

Yep – changing the frame rate and scaling the animation data will always look different from the original animation.
This is because it isn’t possible to preserve the spacing correctly.

Here is just a few examples of the many difficulties….
You have keyframes on your key poses – ie the important story telling poses.  These are not evenly spaced.  Sometimes they are keyed on 1s, sometimes 2s, sometimes…well any arbitrary number of frames.  These poses might not have every part of the character keyed and the handle types are all going to be different (auto, aligned, vector etc)
This will affect things when you scale the animation data.  The aligned and vector types will keep the same tangents, whereas the auto handles will adjust.

Also if you scale this animation data, the new positions might not fall on a full frame (ie – it could land on a sub frame) and therefore the poses you created will not be rendered……the pose near your key pose will.

Say you are slapping the foot down in a walk over 1 frame (@24fps), then you change to 48 fps (haven’t seen that frame rate btw haha).  This happens over 2 frames now.  The handles between these keyframes are now a problem.  Originally you didn’t have to worry about them because it was a subframe that wasn’t read by the computer.  But now that sub frame falls on an integer frame.  So those handles control the new inbetween.  What where those handles doing? Are the vector, auto, aligned??
The only way to make sure the animation isn’t doing anything weird is to adjust them manually.
Sometimes a 1 frame pop might be exactly what you are after – so if you are changing that to 2 frames, you will then need to adjust that animation again.

So what is the solution to all this?

Animate at the correct frame rate.