keyframing problems in premiere

November 20, 2009 4:21 PM

Adobe Premiere Filter: how do I adjust keyframe interpolation to get a title to move the way I want it to? (I can't believe the fairly simple option I'm looking for wouldn't be available...) Exhaustive details inside.

The title in question starts with a couple of words scrolling slowly left (each letter is actually its own title, so they can move independently of each other). Here's what I want to happen to each letter, starting with the leftmost and moving down the line in rapid succession:

A. The letter is moving left at a steady velocity. It has ZERO VERTICAL VELOCITY this whole time, only horizontal velocity.
B. The letter 'drops' by about thirty pixels, accelerating vertically from zero until it hits a certain point. At this point its vertical velocity instantly returns to zero and STAYS THERE. Throughout this step, the horizontal velocity from step A remains constant.
C. The letter keeps moving to the left, maintaining the same horizontal velocity it has had since the beginning. No changes in vertical position.

Here's the problem: each letter gives a little 'hop' before starting step B, and a little 'dip' after ending it. Instead of just falling and then stopping, it rises a few pixels above the "A" baseline, falls thirty pixels or so, then dips a few pixels below the "C" baseline before returning to it.

No matter how I try to mess with the interpolations (linear, bezier, continuous bezier, auto bezier, etc.), the letter ends up doing variations on the same damn thing (unless I try "hold," and then it teleports). I guess this is meant to smooth out the movements of titles and objects, but in this case it doesn't make my titles look smooth, it makes them look terrible.

So, how can I stop this vertical overcompensation? I'm still pretty new to Premiere, so it's quite possible that there's an interpolation technique I'm missing, or a screwed-up setting I haven't noticed somewhere. If not, and there's no way to stop it, then thanks very much... I'm off to find the people who made this program and burn their houses down :)

(Sorry if all that explanation seemed a little too emphatic, it's just that this is driving me batshit with rage. I should have taken screen caps or something.)

posted by Vic Morrow's Personal Vietnam to computers & internet (6 comments total)

Does Premier have "Ease Out" and "Ease In" as motion types?

The way I'd do it in other packages is to create a parent-child and have the parent provide the lateral motion while the child handles the vertical. Each has it's own time line. I don't know if Premiere supports hierarchical motion but in, say, AfterEffects, the parent would be added as a "null" onto which the type element would be a "child." The lateral motion would be programmed to the null and the vertical to the type element itself. The only motion type I'd use would be "ease" as any bezier or curve fit will tend to "anticipate" upcoming motion by, well... hopping a little in the generally reciprocal direction as the primary vector of motion (as you have noted).

If you submaster the type's vertical element and treat it as footage you can do what you want. It's just another method of approaching hierarchical motion.

One other thing is, that without my being able to see what you are trying to do, you may be falling victim to a phenomenon where motion appears to hop but it really isn't. It's just a visual trick of the eye that sees disparate motion (the vertical) as being "rough" compared to the primary motion (the lateral).

I doubt I have helped you at all.
posted by bz at 4:46 PM on November 20, 2009

It's been several rev's since I've messed with Premier but it was not an animation tool like After Effects. Can you get the effect with one letter? If so, do each letter separately and mat them together.
posted by sammyo at 4:57 PM on November 20, 2009

You might have, bz... I'm pretty sure it does have Ease In/Out... unfortunately, I sort of ignored those since they were grouped by themselves on the interpolation menu. When I get back to the saddle on Monday I'll give it a try.
posted by Vic Morrow's Personal Vietnam at 5:01 PM on November 20, 2009

To go on (after thinking about it), I realize that what you are trying to do will probably not work as long as you are trying to insert keyframes for a short-duration event (vertical) within an expanse of two distant keyframes unless those distant keyframes (the lateral motion) are set to linear or some other non-curve fitting motion type (ease out/in). You'll get that windup disturbance if you have any other motion type set any where else on that character element's timeline.

I wish I knew Premiere to know if you can have a different keyframe list for different axes of motion but I am guessing not.
posted by bz at 5:02 PM on November 20, 2009

I am not a Premeire guy as I do everything I can in after effects but it sounds to me like you have a bezier keyframe where you want a linear one.

For a work around set a keyframe one frame before you need to make the first move and make sure that is linear interpolation (both spatial and temporal). If need be you can always animate the tricky section with a linear keyframe on every frame for the tricky bits.
posted by jade east at 5:34 PM on November 20, 2009

"If need be you can always animate the tricky section with a linear keyframe on every frame for the tricky bits."

I often use "HOLD" motion for that stuff ;-)
posted by bz at 5:39 PM on November 20, 2009