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Slow Motion of 30P footage…..
I have some footage that was shot in 30P on a DVX and there are a few shots I would like to slow mo. If I just change the speed on the FCP timeline, it interlaces the footage in an extremely horrible fashion, making it useless. I then decided to attempt the same slow mo rate (50% just for exprimental purposes) in After Effects which did a WAY better job of it. AE seemed to repeat frames instead of attempting to draw info from different frames and interlacing them together the way that FCP did. Even at 50% the AE slow mo looked pretty good.
However, when I rendered the footage from AE and imported it in to FCP, there is an OBVIOUS degradation in the image quality compared to the untouched clip in FCP.
Is this due to the slowing, the AE render settings (Animation / no fields / 30 fps), or the re-render on the FCP time line?
Any formulas to try instead of these? Am I missing something.
J.
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7 Replies
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Turn off the frame blending in FCP. Select your clip that you want changed in the timeline, hit apple j (to change speed), and enter the amount and make sure frame blending is off. Also, are you working in a progressive or interlaced timeline?
For what it’s worth, I was playing with Twixtor the other day, and while it took some playing to get what I wanted, the results were pretty sweet, and this was on really high motion footage shot off a cam truck following a motorcycle (shot 24p). It ain’t cheap, but it won’t break the bank either.
Whichever path you take, good luck
jeremy
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G5 Dual 2Ghz <> 4GB RAM <> FCP 5.02 <> Kona 2ATTO 42XS <> Huge Systems 1.25 TB 4105 Fibre
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I turned off the frame blending and I think it looks worse.
Its a 30P timeline/sequence. -
Have a look at twixtor ( you can download a free demo). Motion effects/time remap are definitely not a strong point of FCP. Like you’ve found, AE will give you better results. SInce you are using an already lossy codec, recompressing it will give you pretty lossy results. Try rendering a straight DV movie out of AE and see what that gets you, it’ll save a recompression step from dv to animation to dv, this way you’re going dv to dv skipping the middle man.
That twixtor plug in works in AE too.
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G5 Dual 2Ghz <> 4GB RAM <> FCP 5.02 <> Kona 2ATTO 42XS <> Huge Systems 1.25 TB 4105 Fibre
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Here is an image of the AE rendered clip on the left and the untouched clip on the right.
https://www.axessmediainc.com/slowmo/
Do Re:Timer and Twixtor maintain the image quality?
J.
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What you are seeing is the RGB (AE) to YUV (FCP) gamma shift that is inherent in most quicktime codecs going from Fcp to AE and back. You can use the 3 way cc, proc amp or gamma correction filters to adjust the levels back down to normal.
Twixtor works natively within FCP and renders YUV so you won’t see those gamma shifts. While you will be recompressing your dv footage when you render the final effect, it’ll keep it in the YUV color space at least.
Make sense?
Jeremy
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G5 Dual 2Ghz <> 4GB RAM <> FCP 5.02 <> Kona 2ATTO 42XS <> Huge Systems 1.25 TB 4105 Fibre
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Yes, it does make sense. I knew something had to be up.
So there is no way to work in AE with YUV settings or FCP with RGB settings? Does Motion use YUV? How are its slow mo controls?
It also looks like a loss of clarity as well even though I stayed in DV/NTSC codec?
I am wondering if that will be less evident after the gamma shift. I will have to experiment with that.
Any thoughts on wether the AE-> FCP -> gamma shift formula is better than the Twixtor -> FCP formula?
J. -
You can tell FCP to ‘always render in RGB’, but your footage will still be captured in YUV when using the dv codec, so it is kind of moot. They only way I know how to remedy this situation is the method we talked about (color correcting the afflicted footage) or digitizing to an rgb codec (such as aja’s 10 bit RGB codec) and tell fcp to render in rgb, but this will require not only capture hardware, a fast array of drives to handle the 10 bit bandwidth, but a dv deck that has an output such as SDI or analog component for capture (bypassing the firewire dv workflow). This still might not create a perfect looking image either.
Motion also works in RGB color space, but if you use motion inside of fcp in that you export directly from FCP to Motion and roundtrip back to FCP from Motion and let FCP render the video, you might stay within the YUV color space, but don’t quote me on that because I’m not sure which application is really doing the internal rendering at that point, Motion or FCP. I must admit this is getting a little beyond my scope of knowledge. If Motion is doing the processing then it will render the video in RGB, if FCP is doing the processing then there’s a chance you are staying YUV. My guess is that no matter where it’s rendering, it’s being sampled to RGB. The fix to this is to include the whole shot you are working with in Motion (or AE) and process that whole shot so the color shift happens to the whole clip and not just half of it. Does that make sense? That way the audience eye won’t perceive the color shift as easily.
As far as Motion’s slo mo controls, I have no idea on that either. I’m not sure if it’s even possible within Motion.
After playing with Twixtor I am a believer. It totally blows the doors off of FCP’s motion effects. It might take some time to tweak the settings, but it’s totally worth the wait. Also, the keyframable time remap allows a lot of flexibility within a shot. You can do a speed ramp up, then slow the footage way down to emphasize a certain motion then speed ramp back up. It’s a lot of fun and much easier to figure out than FCP’s or AE’s time remap, and it works right in FCP’s filter interface which is keeps things a little more simple and contained. Plus, the humor in the Twixtor makes for a good read, even if you hate reading manuals. It’s written to have fun and encourages you to play with the filter. Kudos to whoever write the manual.
I hope all of this helps and that you at least gain something out of this, if not a proper method of attack.
Cheers,
Jeremy
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G5 Dual 2Ghz <> 4GB RAM <> FCP 5.02 <> Kona 2ATTO 42XS <> Huge Systems 1.25 TB 4105 Fibre
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