Getting 120fps to render in slo-mo

[simonov]

I recently bought a GoPro Hero2 specifically to work with its built-in 120fps mode. Specifically, I am trying to capture, with high quality, the action of semi-automatic rifles and shotguns, shells and case flying out, etc. However, I am having difficulty actually getting the clips to render in slo-motion.

I am using Adobe After Effects to render clips. Here is an example of what I am trying to do:

http://vimeo.com/32034936

Now with that video I actually fooled around with the time mapping a little, but the bits where I am actually shooting are supposed to be slowed down (it was shot at 120fps).

The AE comp would be 99 fps (apparently AE doesn't support a higher fps? WTF?), and I would render it to a file at 99 fps. Looked great, but not as slow as the original RAM preview. Then when I uploaded it to Vimeo it would speed back up again.

I tried it again with H.264 format (recommended by Vimeo), but that automatically goes to 60fps and, again, I think Vimeo speeds it up even more to 30fps. That's the version that's up there now.

So what do I need to do to:

1. Render a 120fps clip at, saw, 30fps in AE;

2. Upload it to Vimeo while retaining the proper frame rate.

[poisondeathray]

just right click the clip in the clip bin and interpret the footage as 30p. Use a 30p comp settings, and 30p export settings

this will give you a 4x slowdown because 120/30 = 4

If you interpreted the footage as 24p, it wuld be 5x slowdown because 120/24 = 5. In this case you would use 24p comp settings, and 24p export settings

Note in both these examples, every frame is a real original frame, you're just playing it back slower


if you want more than that, you need to either use lower interpret footage fps settings or interpolate new frames (generate new frames, as if you shot more than 120fps), you can use 1) frame duplication 2) frame blending or 3) frame motion interpolation

AE has pixel motion and timewarp which are examples of (3) .

[budwzr]

Another way to say it is don't "overthink" it. It's the same principle in any NLE for p60, p90, p120, p1000, whatever. Wadaphuk is "time mapping", hahaha, it's "Playback Rate".

That Adobe and Apple love to futz the names of everything so you get lost if you try to use any other product.

[TreeTops]

That clip doesn't look slow-mo at all. Especially the last second of the clip.

[Cornucopia]

No Slo-mo there. Fast-mo and Faster-mo.

IIWY, I'd plop the original 120fps file onto a standard 30fps timeline, then do the time remapping. You want the final output to be standard framerate so it'll show/convert well in other settings (like youtube/vimeo).

Scott