60fps slo mo in 60fps timeline

I'm wondering what the best method is for the following problem:
I have videos shot in 60p. I have been inserting these videos into my timeline which is set for 60fps. One of these clips has to be slow motion. What is the best way to slow the clip down without sacrificing quality?
a) just use the retime feature?
b) create another project with 24fps timeline, drop the clip in, conform, and then export/finalize the project, and then take that clip and bring it into my 60fps timeline?

Please help, thanks

I have been thinking a lot about this lately. Another example: you shoot with a DSLR in 25p or 30p and have some GoPro footage in 50p or 60p.

The answer is: use 50p or 60p in your timeline if you need to do slowmo. If you take a 60p clip (in a 60p timeline) and slow it down to 50%, then FCPX will just repeat every frame 2 times. But if you wish to use optical flow and make the slowmo more fluent FCPX will be able to replace all the repeated frames with computer generated frames.

Optical flow is not the answer to all clips and is quite CPU/GPU intensive, but hey its a free tool within FCPX, so give it a try.

And please note that "conform" is now called "automatic speed" in FCPX 10.1

Thanks mousefarm.

I guess I'll try both methods...slowing the 60p down 50% and I'll try the optical flow too...see which yields better results.

YOu presented an intetesting problem though. If you have 30p footage inside a 30fps timeline....and wanted to add some 60p footage from your go pro, wouldn't you just drop it in the timeline and let FCP drop the necessary frames so that it matches 30fps. Or is there a better way around this?

Is that not backwards? If you choose a 60p sequence then 60fps clips will run in realtime. In order to roll 60fps as SloMo you need to select a sequence frame rate that is slower than the media's frame rate - example; 24fps sequence can roll 60fps media in Slow motion, select conform. It would run slightly slower than half-speed.

I enjoy glide cam shots that are slightly slow - I get the surreal look by shooting 30 fps (29.97) on my 5DmkII and dropping those clips into a 24fps (23.98) sequence and conforming them. The combination of the full-frame glide smoothness and slightly slowed frame rate makes for a nice look.

Let me know if I'm misunderstanding what you wrote.

No. Everything has changed with FCPX

dude is correct, shoot 60fps, drop it into a 24fps timeline, use the Automatic Speed (formerly Conform Speed) to get true, in-camera, all original frame slow motion.

Thanks for the answer but I already understand this. My original question was applying slow motion to 60p video in a 60fps timeline. What is the best method? Mousefarm recommends using the retime option and maybe incorporation optical flow. Would you agree?

Also, my second question is not a slow motion question.
Quite simply, if I have a 30fps timeline and want to use some 60p video in it...is the best option just dropping the 60p video into the timeline and allowing FCP to remove the necessary frames? Or is their a better method that will produce better quality?

Thanks

I agree with Mousefarm - retime using optical flow for best results.

On using 60p media in a 30p timeline, I do not think FCPX is removing frames - you are gaining playback frames within your 30p timeline which a crisp look, (similar to sports 60i look). That's why selecting 60p clip in a 30p timeline and choosing Modify > Retime > Conform, results in slow-motion, because FCPX is then conforming the clip to play frame for frame according to the framerate of the timeline. A 60fps clip in at 30p timeline not conformed is playing a 2x so it is like taking a 30p clip and playing it at double speed which is not the same as removing every other frame.

I was under the impression that if I put a 60fps clip in a 30p timeline...that FCP would remove half of the frames so that it plays at 30fps in normal speed.

You are correct, mgeck, if you put a 60fps clip into a 30p timeline, it will play in real-time which means it will discard half the frames. If you conform the speed (automatic speed it's now called) of the clip, it will play frame-for-frame, resulting in a half-speed slomo.

Yes, if you want slomo of a 60fps clip in a 60fps timeline, you have to slow it down, and the built-in optical flow may be your best bet. However, it could result in motion artifacts depending on the visual complexity of the shot, since the computer will be extrapolating frames. Ideally you can plan for this by shooting with a higher shutter speed/angle to lessen motion blur and avoid complex looking backgrounds for your subject. There are also optical flow plugins that will have more options, as well as After Effects which has its own brand of optical flow. But of course the real way to is to shoot at a much higher fps.

Thank you haysoos for the clear and detailed answer.

Much appreciated.

Rule of thumb with Optical Flow; if the background moves, it may not be a good idea to use it.

Good tip BenB

Ps "That's why selecting 60p clip in a 30p timeline and choosing Modify > Retime > Conform, results in slow-motion"... I think Conform in 10.1 is now called 'Automatic Speed'

for best quality:
may be you could not only use fcpx
cause I've found if I set my 50p clip to 25p timeline, the duration is the same.

may be you should export the your 60p movie as tif sequence in fcpx
than use motion to export the tif sequence to 30p prores movie

than you get the best quality,haha

artofoe wrote: fcause I've found if I set my 50p clip to 25p timeline, the duration is the same.

After you drop it in the timeline, you have to apply the Automatic Speed setting from the Retiming menu. No need to export anything as anything.

yes, that's right!
I just do a test on a sony 4K monitor, frame by frame
the quality is the same from my eyes.
so no need to export them as tif sequence.

By the way, to the OP, I would suggest you actually cut your project in a 30p timeline (29.97 fps). Unless you're going for a "live sports" look or want it to look like a news show or something like "60 Minutes," you are better off in a 30p timeline. You say you want to use a lot of slomo, so you've already shot a lot of 60fps footage. It's always better to NOT use artificial slomo like optical flow if you can help it. Since you've already shot 60fps, you can opt to use that footage for both real-time and half-speed slow motion. If you want to go even slower than half-speed, then optical flow may help you there. The only real difference is that stuff shot at 60fps will tend to have less motion blur, but it won't look bad at all in a 30p timeline.

If you wanted a 24p project, you should've shot most everything at 24p with the exception of things intended for slomo, which could be shot at 60fps (or higher depending on your camera and desired effect) and set to automatic speed so it plays frame-for-frame. In general though, sticking 30fps or 60fps footage into a 24p timeline to play in REAL-TIME will make it play a bit jerky.

It was some snowboarding video that I had filmed with a go pro. So i was hoping to keep it in 60p if possible, but i may put it in a 30fps timeline just to see what it looks like.

Thanks for the information haysoos.

Create a 24fps timeline, use it to slow-motion your clip, export as a 30fps QT clip. Use that in your 30fps timeline. Slower slow motion, 30fps native clip.