Why use twixtor?

Isn´t it possible just to retime in FCPX?
I have seen someone retime in Motion, and then put it back in FCPX. Why don´t they do all the work in FCPX?

Twixtor is widely considered the best retiming software and has been for a long time. It produces excellent results, but it does require more software, is tricky to adjust, and is really, really slow to process, at least it was the last time I used it.

… what I've learned (Twixtor offers tutorials), the main difference is, you are allowed to tell the plugin, what is forground (moving) and what is background (not moving).

What I'm noticing here is (in)famous 'wobble', using FCPX' retime feature: Optical Flow cannot differ btw. wanted and unwanted 'vectorizing'.- So, around me smoothly running soccer-players, the green or people in the bg act like jelly! -

Twixtor should handle that - I don't know, 300$ is way too much for a hobbyist like me! :lol:

I've been trying out some ideas for slomo on the C100...

vimeo.com/67463141

And Optical Flow didn't really do what we'd expect it to do.

A while back, I was doing a similar thing with the basic S&Q slomo from the FS100 where I combined it with The Foundry's Kronos - it's not quite Twixtor, but a darn sight better than Optical Flow. You get what you pay for, and for many 'Free' wins. However, if you're being paid for results, the third party options (Twixtor, Kronos) add more polish and get better results in more situations.

The secret to Optical Flow is that you can't have much movement in the background. It is best to start by shooting 60fps in the camera, then edit in a 24fps timeline, and use the Conform command first. Then retime. But yes, too much background motion will cause issues with Optical Flow.

BenB wrote: The secret to Optical Flow is that you can't have much movement in the background. …

Thanks for that hint!

prob here: usually I have to pan like mad => soccer game.
It's not those 'epic' skater stunts on a fix ramp, etc.

but, for 'beauty shots' I'll try your suggestions ..........

OK, here's an idea. Shoot 60fps, drop it into a 24fps timeline, use the Conform command to get your in-camera slow motion. Then slow it down from there.

If you still want Optical flow, retime the clip using Frame Blending, then Command-drag the clip above itself. On that top clip, use CoreMelt's amazing SliceX to mask out the main action, and then apply the Optical Flow to the top clip.

I've never tried that, just a thought that popped into my mind.

Besides of that Twixter is still getting updated where Optical Flow is a old dog from the Shake days.

From my point of view I can't recommend anything more than Twixtor (I always need slomo).
But it's difficult to learn and sometimes difficult to handle. For real good results you often need more then just Twixtor as you need to split the actual clip into several layers to handle those different with the Twixtor settings.
I would use Twixtor with AE cause there are more options to setup the source. For example to make 3x3 mirrored matrix of the source, crop it to make it only a bit bigger than the actual clip. This will help have "clean" results at the edges of the final clip.
Two years ago I retimed a 90 Minute clip from 50fps to 1000fps. Took a week to setup and a week to render (on one machine)

-Andreas

Thank you for inputs! Really helpful!

I´m shooting a street race(road bike) tomorrow, and I need some slow motion shots. Haven´t decided which program to use, but should I just go for 60fps in all my shot to be on the safe side?

How much reduction do I get if I shoot 60fps, and put it in a timeline with 25fps?

Neguah wrote: … How much reduction do I get if I shoot 60fps, and put it in a timeline with 25fps?

hmmmm, really? .....

60/25=2.4
or, in words: your clip runs two-and-a-half slower.
or, in percent 41.7% of its original speed ...

You know... It´s a good thing your math is good. Besides that... I´ll leave it with that.

A guy told me that 30ps to 24fps is 6% slow. Now tell me, how to I get the 6%?
Do it slows down less if you convert it with cinama tools?

Can I somehow convert from 60 to 25fps without loosing as much speed?

Neguah wrote: … A guy told me that 30ps to 24fps is 6% slow. Now tell me, how to I get the 6%?…

no idea, 'cause that is plain wrong.

what is 50%? half
10%? a tenth.
5%? a twenty-th

so, to create a 5% (five is very close to six …) slowmo in a 24fps project you would need 20x24frames = 480.
not 30.

a 30fps recording delivers 6 frames more per second than the 24fps project needs.
6 is a quarter of 24, so 75% 'slowmo'.
not 6%.

rule-of-three, 4th grade, percentage calculation, 6th grade.
sorry to say that.-
(my son is in 7th, so I'm up2date ..... )

Shoot 60fps, conform in 24fps timeline, results in 40% slow motion.

Math is sometimes simple. I have never thought of putting a 30fps og 60fps in a 24fps timeline. Because of that I have never even thought of what happens if I figure out to try. Maybe I´m not so smart. But I don´t care if what I am. Because I am who I am.

So, when this guy told me 6%, I brought up my calculator. I came up with 80% of 30fps. 24fps is 6 frames less than 30fps. 6/30=0,2=20% slowmo.
Of course, I trusted the man with the 6%. And of course, not smart enough to figure out the 60fps and 25fps by myself.

BenB wrote: Shoot 60fps, conform in 24fps timeline, results in 40% slow motion.

And if I find out that 40% slow motion is to slow, I need to stick with the 60fps? No way to conform 60fps to 24 or 25 without reduction?

"Conform" uses all original frames, that is all. If you slow it down more, you're getting slower slo-mo still with higher visual quality. To get faster slo-mo, you're going to be dropping frames from the original. But still should be better quality than slowing down without the "Conform" first, which must create faked additional frames.

Method 1 - Conform, decrease duration, dropped frames.
Method 2 - Re-time without conforming, increase duration, adding faked frames.

I tried putting my 60p footages in a 24p timeline, and then conform. However. It was to slow for me. I don´t want every clip to be that slow. And if I sped up(speeded up?) the clip, or left it with 60p without conformin, it got very bad.

So, I put the 60p clip in a 60p timeline. When trying to slow down the clip, I noticed the problem with optical flow because of movement(panning the camera) in the background. That´s ok. So I probably need Twixtor for that.

But, when I had my camera on a tripod, and try to film the riders in a sprint every frame became blurry. So, retiming with optical flow was ok, but the clip with slowmo was blurry because of all the frames being blurry. Every time I tried to pause(before slowing down) it came out blurry.
Why is it blurry? Do I need higher fps? The riders were going in perhaps 60 kph.

Neguah, not sure if you got everything right about conforming and retiming. Please try this:

1.) Drop your 60fps clip into a 24fps timeline.

2.) Conform the clip speed of 60fps.

3.) Now select that clip in your timeline and hit CMD-R to use the retiming tool.

--> you'll see a green bar appear above the clip. Use the right handle of that bar to pull the clip longer (i.e. make it slower) or push that clip shorter.

This means that you are not stuck with the slomo. You can choose every speed you want. If you use CMD-R and then speed the clip up to roughly 250% you'll be back to original speed. Same if you import 60fps into the 24fps timeline without conforming.

Does this make sense to you? Please try and ask if I did not explain properly.

Overturf wrote: Neguah, not sure if you got everything right about conforming and retiming. Please try this:

1.) Drop your 60fps clip into a 24fps timeline.

2.) Conform the clip speed of 60fps.

3.) Now select that clip in your timeline and hit CMD-R to use the retiming tool.

--> you'll see a green bar appear above the clip. Use the right handle of that bar to pull the clip longer (i.e. make it slower) or push that clip shorter.

This means that you are not stuck with the slomo. You can choose every speed you want. If you use CMD-R and then speed the clip up to roughly 250% you'll be back to original speed. Same if you import 60fps into the 24fps timeline without conforming.

Does this make sense to you? Please try and ask if I did not explain properly.

This was very good, Overturft! Thank you for your quick answer!

I did what you explained. But when I speed up the clip to 250%, or to original speed, the clip was not good at all. I can´t explain it(not sitting with my Mac right now). But I´ll try again when I get home. Maybe I missed something.

Thanks again, Overturf!

And one more thing. I shot 60 fps with shutter speed 125. Would it help if I shot with shorter shutter speed, let say 2000 for the fastest footages(when the riders were going really fast?