Moho Forum

I have an idea about frame rate, but I'm not sure I'm thinking about all the factors correctly.

I'm animating a scene with a lot of action in a small amount of time. The scene is animated at 24 frames per second. Timing (the location of every keyframe) is critical. The action must not be too fast, but also must not be too slow.

Here is an example.

An object starts flying on frame 56. If the object hits the point of impact on frame 60, the movement seems too slow. But if I the object arrives on frame 59, the movement seems too fast. Those are my choices: too slow or too fast.

But what if I animated the scene at 48 frames per second? In a sense, it would be similar to animating at 24 fps, but with the option to animate on the space between frames. Right? This could solve my problem with my action scene. At 48 fps, the numbers are doubled. So that changes the math in my action scene to 120 is too slow and 118 is too fast. That means 119 would be perfect.

Am I right?

Are there any downsides to this?

Should I use 24 fps for all normal non-action scenes, and 48 for the action scenes, and then change all rendered 48 fps movies to 24 fps in my video editor? Or what?

This reminds me of a documentary I watched on hand-drawn animation. The animators animated on twos, generally. But if there was important movement within a fraction of a second, the animators would animate on ones.

Thanks for your help.

No, this doesnt work, because: any rendered video must have a consistent frame rate (24, 25 or 30, usually), and the channel which shows it (TV, stream, whatever) must be able to replay it with that.

For a problem like this there's the art of multiples and smears.

If the timing is crucial for matching a sound/beat, it actually reads more in sync to have the visual land a bit early. I haven't come across anything that couldn't be timed in 24 fps.

Dang.

Oh well, it would've added another technical complication an already complicated process, so I'm only a tiny bit disappointed.

I guess the simplest solution to my timing problem is being less picky when sliding my keyframes back and forth.

And do the multiples and smears when necessary, like you said.

Thanks.

synthsin75 wrote: ↑Tue Jul 27, 2021 5:08 pm If the timing is crucial for matching a sound/beat, it actually reads more in sync to have the visual land a bit early.

Thanks for the tip. If I can't decide which direction to slide a keyframe when tinkering with the timing, I'll opt for early.

I like snappier animation anyway.

I don't think there's any real advantage to animating a 2D cartoon at 48 fps. You can try it and see if you like it better but, IMO, there's typically not enough motion or depth involved to make the higher frame rate noticeably better to most people.

If the intent is to smooth out timing within Smart Bone Actions, then yes, you should use more frames inside the Action. Note that this isn't the same as working in a specific frame rate (like 24 vs 48) though.

When animating a Smart Bone, the Action plays back at the relative rotation of the Smart Bone, so the speed can vary during an animation. When the rotation is short, frames in the Action are dropped, and when the rotation is long, the existing frames are stretched. Here's the thing: animation inside the Action is interpolated and plays back smoothly, however, on the Mainline, if the animation is played slower than animated, Moho will not calculate sub-frames, only whole frames, so the playback can appear 'steppy'. If you're seeing this 'steppy' effect happen in your animations, it means you don't have enough whole frames in your Smart Bone Action to play it back smoothly at the rate your playing it back with the Smart Bone rotation in the Mainline. To fix this, you simply need to extend the duration of the animation Action so you always have enough frames for smooth playback.

If your next question is, how many frames is appropriate for smooth playback? It really depends on how you intend to use the Smart Bone. For example, if you're using a Smart Bone to control a character's blink, and you only want two positions, open and close, then you only need two frames in your Smart Bone Action. This way, no matter how slowly you animate the Smart Bone, you only have the two positions, open and close. But if you want to make the blink a little slower and smoother, then you want to increase the animation to 6 frames. If you anticipate animating your character doing a very slow flirty blink, then you may want to increase the animation to 24 frames...more if it's going to be a ridiculously slow blink. (Maybe the character is falling asleep?)

As for mixing animation frame rates depending on the activity, some big productions will do that, but the end result is still played back at 24 fps or at whatever frame rate the entire production is in.

There was an animated Nissan commercial I worked on back in 2001, and we animated almost everything at 12 fps and when we rendered out the movie files for editorial, we stretched the animation to 24 fps so basically every frame was doubled without any kind of interpolation. Since this was mainly a cel-shaded 3D production, doubling the frames helped make our animations look more like a normal 2D cartoon. However, some dramatic shots involving helicopters, drones and sweeping camera moves, looked way to 'steppy' at 12 fps, so we rendered these shots fully animated at 24 fps. But in the end, it was all technically 24 fps on our editorial timeline.

If anybody is curious, some of the helicopter footage is on my 2010 reel. One of these days, I may cut another reel with more footage from that commercial.

Edit: Hmm...I just looked at it and I can tell I animated the one helicopter scene on my reel is at 12 fps, so that's really not a good example. Oh well.

A better example might be almost any decent action-oriented anime show...most of the animation will often be animated on 2's (12 fps) or even 4's (6 fps) and the action scenes will be animated at full 24 fps...but it's all played back editorially at 24 fps.

Greenlaw wrote: ↑Tue Jul 27, 2021 5:43 pm A better example might be almost any decent action-oriented anime show...most of the animation will often be animated on 2's (12 fps) or even 4's (6 fps) and the action scenes will be animated at full 24 fps...but it's all played back editorially at 24 fps.

Thanks for information. I had noticed in anime the different frame rates. That was helpful example.

Just to be clear, does editorially mean...when edited in a video editor, like iMovie or Blender?

One more vocabulary question, if you don't mind. You used the word "simulation" recently when describing Moho's physics. Can you explain which part of the physics is the simulation? In my mind, everything animated is a simulation, but I suspect you meant something more precise, like the math calculations are the simulation, or the moving shapes are the simulation.

I think a good chunk of my animation vocabulary comes from your posts on this forum. Thanks.

Hoptoad wrote: ↑Tue Jul 27, 2021 7:43 pm Just to be clear, does editorially mean...when edited in a video editor, like iMovie or Blender?

Yes, by 'editorial', I mean the final edit in the video editor program. The industry standard is usually 24 fps because film has been 24 fps for so long, but it can actually vary depending on region and media platform. But regardless, the final output is rendered at one frame rate for the whole production, whether it's 24, 25, 29.97, 48 or whatever.

Anything animated at a lower rate is essentially stretched to fit the final frame rate and without any interpolation, so you wind up with held frames. So, for instance, anything animated on twos (or 12 fps) basically has each frame held for 2 frames for a total of 24 fps.

IMO, if you're animating rigged puppets in Moho, I don't see the point in animating at a lower rate other than 24 fps, unless you're trying to match the look of other footage animated at a lower frame rate, like hand drawn FBF animation from another animation program. Then you might want to set Moho's frame rate to match. But in the end, everything will probably get imported to final editorial timeline stretched out to 24 fps (or whatever the final frame rate is.)

One more vocabulary question, if you don't mind. You used the word "simulation" recently when describing Moho's physics. Can you explain which part of the physics is the simulation?

'Simulation' is the result of using Moho's Physics. I might have used the term to describe when Moho is processing the physics animation. In other words, when you use Moho Physics, you're simulating how physics work in the real world.

When Physics is enabled in Moho, the 'simulation' is created when you click the Play button and Moho recalculates this every time it loops back. When you bake the keys during playback, and then disable Physics, Moho is no longer simulating...it doesn't need to until you decide to change something that should affect the simulation.

Edit: Earlier I wrote about After Effect's Posterize Time plug-in, but my description was incorrect. (This what happens when I try to write with a monster headache.) I removed that line but, FYI, here's what Posterize Time actually does:

Posterize Time lets you easily reduce the motion in footage, kinda like how a posterization filter in a graphics program can reduce the color range in an image. For example, if you have footage that was rendered at 24 fps, but you need to look like it was animated on twos, you can change the setting from its default 24 fps frame rate to 12 fps. The result will be every other frame dropped from the footage, with the remaining frames held for 1 frame. This is super useful, for example, when you need to match your 24 fps Moho footage to FBF footage animated on twos in another program. Basically the opposite for what I described earlier. Sorry for the misinformation.

To stretch footage in Ae from 12 fps to 24 fps, you can simply add a Time Stretch set to 200%. Ae will stretch the footage and duplicate frames to fill the blanks.

Thanks for explaining.

I worked on a scene today that employed Moho's physics. I ran the simulation several times until I liked the results, then I baked the keys. I expect to render the animation tomorrow for my 24 fps editorial timeline.

Dude, a couple months ago that paragraph would've made very little sense to me. Progress!

Glad to help!

BTW, I had some incorrect info in the previous paragraph, so I revised it.