Compressor, “Optical Flow Technology,” 24p to 29.97 – horrid artifacts – semi-rant

[Rafael Amador]

[John Heagy] “For a 30 sec spot in this case yes. For a 5 min or longer interview, absolutely not as the audio will drift out of sync.”
There is not any drift when conforming on CinemaTools.
Video and audio track keeps the same duration.
Video changes the time-base and audio changes the sample rate.
rafael

http://www.nagavideo.com

[John Heagy]

[Rafael Amador] “Cinema Tools changes the sample rate.”

I didn’t think Cinema Tools did that… good to know.

Since CT does not render out a new movie, it is just a sample rate metadata change. If audio was recorded at 48K, a 24 to 23.97 conform would “pulldown” the audio to 47952. To avoid this one could record audio at 48048 so it would pulldown to 48000.

Compressor can pulldown to 47952, re-sample to 48000, and add 3:2 in one step.

John

[Kevin Reiner]

Dave, thanks for this workflow. It just helped me out.

My videographer insists on shooting 24p even though I argue for 30p to make my life easier. (filmic shmilmic)

So should I just start with a 30p sequence and edit the 24 footage into it? Or should I make your method be the final step and stay 24 up to that point?

… and if so, what if I have an AE sequence that is to be edited into the spot? Do I do that in 29.97 or 24.98?

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SOFTWARE
Mac OS X 10.6.5
FCP 7
After Effects CS5
Boris Continuum
Sapphire Plug Ins
All Trapcode Plugs
Zaxwerks Invig

[John Heagy]

[Kevin Reiner] “So should I just start with a 30p sequence and edit the 24 footage into it?”

No, edit in 24p and then add 3:2 to the finished 24p master. This is the only way to create an unbroken 3:2 cadence across edits.

[Kevin Reiner] “My videographer insists on shooting 24p even though I argue for 30p to make my life easier. (filmic shmilmic)
“

The “Cult of 24” is strong.

Hoping the 48fps Hobbit is able to deprogram those who suffer from it.

John

[Kevin Reiner]

So even if I make a smooth 30p AE movie to be inserted into the 24p sequence, frames will be thrown out, just to add pull-down frames on final export.

Makes total sense. 😉

Mac Pro 2 x 3 GHz 6-Core Intel Xeon
32GB Memory
Dual-channel 4Gb Fibre Channel PCI Express card
Dell Display (23″ flat panel)
ATI Radeon HD 5770
AJA Kona LSi SD/HD capture card
Rourke 16 TB
Flanders 2460

SOFTWARE
Mac OS X 10.6.5
FCP 7
After Effects CS5
Boris Continuum
Sapphire Plug Ins
All Trapcode Plugs
Zaxwerks Invig

[Jeff Jordan]

I’ve been wondering, is there any way to convert from 24p to 29.97i that automatically recognizes cuts and will not use a mixed frame at the cut? Even when using AE, whenever a cut lands on an interlaced frame, it blends the two different images together into one interlaced frame. Or do most people just live with this artifact?

[John Heagy]

I think he understands that. He’s asking if the 3:2 cadence can be “reset” at cut points to avoid mixed cuts. The only way to do this is process every shot separately then put it back together. This avoids mixed cuts buy creates broken cadence potentially at every cut across the show.

The best way is to edit the 24p timeline on frames that don’t produce the mixed cuts.