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Is it possible to speed up camera movement, without it looking sped up?

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ryan elder
Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 12:25:23 am

There are a few times, when I want to move the camera, really fast, faster than a camera operator could move it. I was told that I should speed up in post, but it always looks obviously sped up in post, and I can't get it to look natural like it was shot that way.

Even if I add motion blur, it still feels like a post effect of speeding it up. Is it possible to speed up camera movement, and make it look natural, like it was actually shot that way, when it wasn't?


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Dave LaRonde
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 12:45:45 am

One way to do that is to slow down the subject's motion as the camera moves. Then as you speed up the shot, the motion looks more normal.

If it sounds difficult to do as you shoot, you're right.

Dave LaRonde
Promotion Producer
KGAN (CBS) & KFXA (Fox) Cedar Rapids, IA


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ryan elder
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 12:49:25 am

Okay thanks, this was the idea that I was going to do but wanted to do tests without actors first to see if it will work. But even if there are no moving subjects or people in the shot, it still looks like it's been sped up and not natural.

Here is a test I did. The first is sped up without motion blur, and the second has the motion blur added. But it still looks like it's been sped up, even if there are no people in it:







Or is it just me?


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Mark Whitney
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 1:48:32 am

How are you doing the speed up?

The Re:Vision plug Twixtor handles things like this pretty well for example.


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Steve Bentley
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 2:11:32 am

Also that motion blur looks pretty steppy - go look at one frame. Its pretty hard to motion blur after the fact because you would have to blur each object separately because they are moving radially out from the camera center and rotationally and laterally as the camera weaves around. A radial blur set to zoom would get you closer.

But as Mark pointed out, Twixtor or RealSmartMotion blur can figure out every object's own blur because it compares frames pixel by pixel. And this scene is the perfect use: Twixter and RSMB have trouble with objects suddenly coming into frame since there is no "before" frame for that object to compare things to. But this shot has everything in frame to start and it all leaves frame eventually.

If you did this for real with a 180 degree shutter, things would be really really really blurry at the edges (think: unidentifiable smeared objects as a still) and less so at the center. So a global blur doesn't always work.

When we do this for "The Flash" we also add little trailers at pointy edges and streak those points a little longer You can either make a mask or just let a crushed luma key pull out some details that you streak longer than the radial blur for the whole scene. (if that's what you're going for). It really adds a sense of speed and covers other sins.



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ryan elder
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 2:20:03 am

Oh I was cutting out frames and then adding motion blur to the frames that were left.


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Steve Bentley
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 2:27:31 am

I always pull out a frame of 70mm film from the Imax film Catch the Sun when I'm trying to explain this to the guys here. If you see a bunch of these frames in order you know you are on a roller coaster. But as a single frame held up to the light, its just a blurry mess and you have no idea what you are looking at. Don't underestimate just how blurry it's gotta be.



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ryan elder
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 2:44:42 am

Okay thanks, but what does the blurriness have to do with it?


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ryan elder
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 2:46:27 am

As for adding blurs, I didn't add a 'global blur', I used the Timewarp plug in After Effects as tutorials were telling me to, to create motion blur, but is Timewarp a bad choice?


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Steve Bentley
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 7:47:36 am

I missed this middle post about time warp. Did you use "by frame" or "by pixel motion"? What did you set the shutter angle to and how many samples? I've never actually used Timewarp to speed things up, usually we're using it to make up frames that never existed - when a clip needs to run longer (which it can do brilliantly).
So the motion blur in the plug in might do a good job if you set the method to "pixel motion" and cheat with the blur. Because its a digital shutter in the plug in you aren't limited to a max 360 degree opening (in other words no shutter). So you can crank that value up to crazy numbers to increase the blur. But you might hit a limit as you will need more samples to make a large shutter angle work, and you may need more samples than there are frames in your clip. Watch the luminence too. It may increase from a too wide shutter angle. Use "Correct for luma changes" if it does.



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ryan elder
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 1:38:00 pm

With timewarp, I set the shutter angle to 180.00 at 5 shutter samples. I set the method to pixel motion. I went by a tutorial to get motion blur, but are these not as good of settings?


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Steve Bentley
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 2:48:25 am
Last Edited By Steve Bentley on Mar 26, 2019 at 7:36:44 am

If things are moving really fast the camera's shutter isn't fast enough to freeze them and make them sharp in a single frame. So things that move fast end up being blurred. In your scene everything is in a sense moving fast relative to the camera because the camera is moving fast (or would have been if you could have shot the push in fast enough).
The reason your version doesn't look sped up is because the blur/smear level doesn't match the perceived speed.



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Dave LaRonde
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 4:25:40 am
Last Edited By Dave LaRonde on Mar 26, 2019 at 4:27:09 am

It doesn't help that the changes in speed are instantaneous, either. One one frame, you're moving at 10 mph, the next you're doing 180. There's no acceleration or deceleration. And that's tough to do.

Dave LaRonde
Promotion Producer
KGAN (CBS) & KFXA (Fox) Cedar Rapids, IA


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ryan elder
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 4:53:31 am

Oh should I have acceleration and deceleration? What if I don't want that and want a straight speed in the move? But I guess that acceleration and deceleration would help sell the realism?


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Dave LaRonde
Re: Is it possible to speed up camera movement, without it looking sped up?
on Mar 26, 2019 at 5:05:46 am

A really hot, badass muscle car can go from 0-60 in 4 seconds.
You're going from 10-180 in 1/30 sec. I'll let you figure it out.

Dave LaRonde
Promotion Producer
KGAN (CBS) & KFXA (Fox) Cedar Rapids, IA


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Dave LaRonde
And another thing...
on Mar 26, 2019 at 2:31:49 pm

You've doubtlessly seen speed changes in videos. Almost without exception, the changes are instantaneous. You almost never see acceleration and deceleration.

There's a reason for that: instant speed changes are a whole lot easier to pull off. Speed ramps are extremely difficult. But you DID want this to be realistic looking, and that means speeding up and slowing down.

Dave LaRonde
Promotion Producer
KGAN (CBS) & KFXA (Fox) Cedar Rapids, IA


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ryan elder
Re: And another thing...
on Mar 26, 2019 at 4:38:55 pm

Okay thanks. I suppose it's okay if it is an obvious speed ramp, as long as the audience doesn't mind. You seem them in movies like The Fast and the Furious movies, which looks kind of cheesy like a gimmick, so as long as it doesn't look gimmicky.

But if it does look gimmicky, then I could accelerate and slow down later. However, is there a way to do that evenly and gradually in after effects, so it looks more natural, rather than just cutting out frames and guessing?


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Steve Bentley
Re: And another thing...
on Mar 26, 2019 at 4:50:22 pm

Don't pre trim the frames for AE. Let it have them all to work with. The time warp effect looks at everything to make the new frames. In newer versions of AE (which you may have) the enable time remapping feature has most of the tools that time warp has. Simply keyframe either effect using frame numbers (in the speed control area in the TW effect). The idea is: what frame number from the clip do I want to have show up on say frame 100 of the time line. Then later, what frame from the clip do I want to show up on frame 200 of the time line. From there you can ease the keyframes to your hearts content in the graph editor (in either TW or enable time remapping).
As for camera shutter angle, 180. Degrees is pretty standard for any shoot. I was thinking more like 5000.



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ryan elder
Re: And another thing...
on Mar 26, 2019 at 5:09:01 pm

Okay thanks. But since I am trying to speed up the motion, would I want the program to create new frames? Wouldn't that just make the camera movement take longer if there were new frames as oppose to cutting out frames, for fast motion?


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Steve Bentley
Re: And another thing...
on Mar 26, 2019 at 6:10:48 pm

Technically every frame should be a new frame, made up from the frames that have to work with. If it not then it will look unevenly steppy since there are only a finite number of frames to pick from.
Yes there will be less frames than what you had to began with but each one of the new frames should be a combination of many of them since the "smear" will incorporate details from across a wide section of time. (that's the sample rate in time warp)



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ryan elder
Re: And another thing...
on Mar 26, 2019 at 6:41:39 pm

Okay thanks, but why does there need to be new frames if I want to speed it up? You say there will be new frames, but I can't figure out the 'why', as to why that needs to be?


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Steve Bentley
Re: And another thing...
on Mar 26, 2019 at 6:51:25 pm

Every frame of the speed up will need information from the frames that get "compressed" down in time to make up that frame and the smear that is the simulated blur. It won't look like any frame that has come before so therefore its a "new" frame. You've already tried just cutting out frames and going with whats left and that didn't work so again the frames we see will need to be "new". There will be less frames than in the original but all the new frames need to be combinings of the old.



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ryan elder
Re: And another thing...
on Mar 26, 2019 at 7:37:58 pm

Oh okay, I still considered the left over frames to be the same frames, but just with motion blur added on top of them, or at least that is how I saw it. But if I shouldn't be taking out frames in order to speed it up, which feature do you use to do so, if taking out frames is not the answer?


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Steve Bentley
Re: And another thing...
on Mar 27, 2019 at 4:11:27 am

Let AE do it for you with either TImeWarp or Enable Time Remapping. I think the aforementioned Twixter will probably do a better job but I can't guarantee it. Every clip has its own unique issues.



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ryan elder
Re: And another thing...
on Mar 27, 2019 at 4:42:55 am

Okay thanks, but when I let timewarp do it for me, the example I posted before, is what you get, and that wasn't very good, was it? Or am I missing something?


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ryan elder
Re: And another thing...
on Mar 27, 2019 at 4:44:23 am

Plus when you let timewarp do it on it's own, it's not adding motion blur to every object separately, like it was said that it should be, is it?


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Steve Bentley
Re: And another thing...
on Mar 27, 2019 at 4:45:55 am

I think you pre cut down the frames though in the previous attempt. No? The only way to get the proper motion blur is to use Twixter or RealSmart Motion blur.



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