Delivering in multiple frame rates! (Conform with AE)

[Walter Soyka]

[noah campeau] “To make the 25fps deliverable:
– Import and conform 29.97 fps footage to 25fps
– Time stretch footage to match the duration of the original 29.97 piece”

This will give the same result as just dropping your 29.97 fps footage into a 25fps comp and enabling one of the frame-blending modes. There is no need to re-interpret the footage at a different rate, then re-time it.

However, this will force Ae to either drop 5 frames per second, or to synthesize nearly all new frames. 30 > 25 is a pretty hard frame rate conversion to do with motion estimation.

Walter Soyka
Designer & Mad Scientist at Keen Live [link]
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
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[Tristan Summers]

Hi
Also, just asking around.
Shooting at 60p, you would need to increase the SHUTTER speed.
I don’t fully understand why.
So the result conforming down will still be stuttery.
Think Gladiator
super sharp
no motion blur to smooth things out
So actually shooting 24p will probably produce better results.
But unless you are familiar with American Cinematographer panning speeds, avoid pans like the f***ing plague
Horizontal camera motion will stutter even if it is super slow.
I don’t think you will need it for this, but just to be aware of…

adding motion blur with TimeWarp can help though
Speed set to 100% but with motion blur on uses optical flow to produce pretty good motion blur. Not as good as Nuke but hey

[Tristan Summers]

Think I am understanding something here.
Higher frame rate obviously means the shutter will have to be open for less time.
Hence there will be a lot LESS MOTION BLUR.
So the image gets sharper.
This can lead to MORE stuttering.
If you then lose frames taking it down to 30/25 it gets more choppy

The extra motion blur shooting at 24 actually helps keep it smooth.

24 divides nicely with pull down to 30 and speeds nicely up to 25
You don’t usually notice the extra doubled frames

60 chops nicely in half to 30 but not sure it can be put in to 25 so easily.

But the softening you et with retiming may actually be a good thing and increase motion smoothness

In a time of multiple frame rates, it would be good to get some tutorial references to point towards best practice on this and similar issues.

Noah and I are from a graphics not a shooting background, so we are thinking about timelines not lenses, which may not be helping

[Chris Newman]

You mean deliver 29.97 interlaced, as this wouldn’t work if he needed 29.97 progressive, right?

To deliver 29.97 progressive, I would recommend shooting at 59.94 with 1/60 sec shutter speed, edit at 59.94, output 29.97, get edit approved, inverse 3:2 pulldown to 24, speed up to 25.

[Tristan Summers]

why wouldn’t it work to 29.97p? there is no interlaced source material

[Chris Newman]

I was intending to reply to suggestions that said:

“You could shoot 24 fps use normal 3:2 pull down to get the 29.97 and slow it down for 25.”

3:2 pull down creates a 29.97 interlaced output, so each source frame is held for 2 or 3 60 Hz fields, which is pretty smooth. If you try to do this outputting to 29.97 progressive, you duplicate 1 out of every 4 source frames, which looks pretty choppy.

[Noah Campeau]

Thanks for all the suggestions, seems like I have some options.

After filming some test shots on my 5D Im pretty happy with the results after following the workflow I mentioned above.

It makes sense to shoot in 60p, as the liquid is going to look a tad better when slowed down by 50%. I will conform the footage down to 29.97 to do my edit and grade. Then to make the 25 version I will drop the 29.97 into 25 timeline with frame blending enabled. Playback is smooth, no dodgy frames.

It will be a completely different setup/camera etc for the real shoot, so hopefully I will get similar results.

[Tristan Summers]

So if normally a 60fps would have 120 shutter speed, if slowing it down, maybe shutter should be 60 to get the right feel of motion blur?
Re. Pulldown interlacing. Oh, yeah, oops, hmmm….