Compressor Settings: 60i to 23.98P for slow motion

[Russell Lasson]

Unfortunately, Compressor isn’t the right tool for this.

Fortunately, Cinema Tools, which also comes with FCS2, is the right tool.

You said that you shot the original footage at 30P. So open up the clip in Cinema Tools and select Conform, the select 23.98.

This will tell the quicktime file to play back at 23.98fps instead of 30P. It doesn’t change the frames at all visually, but simply changes how many frames per second it will play.

Make a copy of your clip and test it to see if you like the results.

WARNING: Your audio will be messed up. So if you want your audio to match, you’ll have to fix that in an audio program.

-Russ

Russell Lasson
Kaleidoscope Pictures
Provo, UT

[Matthew Nelson]

[Graham Futerfas] “Can someone please help verify the correct settings in Compressor to convert footage from 60i to 23.98P so that it looks like 60 frame slow-motion?”

There is no setting in Compressor or CT that will make 60i look or act like 60p. When the footage is deinterlaced the video goes from 60 fields/sec to 30 frames/sec. So the slow motion you will get is the 25% speed difference between 23.98 and 30. Any further slowing of the footage will have to be done by using some form of speed shifting like optical flow or simple speed change with frame blending.

Matt

[Jeremy Garchow]

What Russell says (although your fields will be kind of screwed) but also there’s this ole gem:

https://rarevision.com/v1/articles/slow_motion.php

[Graham Futerfas]

Thanks, Russell.

I’ll admit that I’m not sure that Compressor is the right tool for this, but I don’t think Cinema Tools will do what I want either. I did try it, though, and thanks for the tip — I’ve never opened Cinema Tools, either. I could get 30P to play slightly slow motion when conformed to 23.98. I didn’t realize it was going to modify the original clip though, so I made duplicates.

I’d like to create 60 frame slow motion over 24 frame playback, though. I shot both a 60i test and a 30P test. In theory, I can do one of two things: take the 60i footage, deinterlace and use the fields to create new whole frames and play back over 24, or take 30P and double the frames using frame interpolation, and then play back over 24.

I know there is some new high-tech motion interpolation mojo in Shake and Compressor that I want to take advantage of. Of course, both options I have above will involve creating interpolated pixels, because I’m either reconstructing missing fields or in-between frames. I don’t have Shake, but I think Compressor might be able to do this because I technically want to convert one thing into another and whatever information is missing I want it to create.

Thanks for taking the time to respond… Final Cut crashed on my last Compressor attempt, so I’ll try it again. I think I got it close on the previous try, but some of my settings were wrong (200% instead of 250%).

Best,
Graham Futerfas

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Graham Futerfas
Director of Photography
Los Angeles, CA
http://www.GFuterfas.com
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[Graham Futerfas]

Hi Matthew, thanks for the response.

According to Apple, Compressor incorporates Optical Flow technology to allow for re-timing footage.

https://www.apple.com/finalcutstudio/compressor/conversions.html

I understand what you’re saying about 60i to 30P. They’re both technically 29.97 fps.

I know I can ask Compressor to retime the footage. I’ll test both the 30P and 60i footage to see what’s better. Thinking about it, though — with 59.94 fields to work with (all scanned in sequence temporally), the software only has to create half of a frame from one existing field. If using 30P, it has to take a whole frame and interpret an entire frame to get to 60P. I wonder which would yield better quality?

I understand that neither is ideal, but the HPX3000 doesn’t shoot 60P, and if I want some slow-motion for a project, I’d like to be able to offer it to the director as a possibility with the caveat that it won’t be as great as the 23.98 footage. How bad would it be? We get away with a lot in this business. 🙂

Best,
Graham Futerfas
(and every time I post I seem to fall behind on the thread…)

—
Graham Futerfas
Director of Photography
Los Angeles, CA
http://www.GFuterfas.com
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[Matthew Nelson]

Following the strategy in the article Jeremy posted try using the frame controls of compressor under retiming control setting the duration to 200% with better motion compensation.

Matt

[Matthew Nelson]

Graham

Here are the steps I took to get slow motion footage from 60i. Thanks Jeremy for that article.

In Compressor create a new Quicktime movie setting.
In Encoder select the video settings. Since you were using ProRes HQ I selected that then changed the frame rate to 60.
In Frame Controls I selected Better for resize, progressive for fields, better for deinterlace with adaptive details on, anti alias and detail I left at 0 for render speed reasons. Rate conversion I set to better with duration set to “so source frames play at 60.00fps.”
Rendered the QT.

Open the new QT in Cinema tools and conformed it to 23.98.

Not as good as true 60p but a heck of a lot better then frame blending. Let me know what you think.

Matt

[Matthew Nelson]

[Matthew Nelson] “In Encoder select the video settings. Since you were using ProRes HQ I selected that then changed the frame rate to 60. “
Change the frame rate to 24.
[Matthew Nelson] “Rate conversion I set to better with duration set to “so source frames play at 60.00fps.” “
Set the duration to 200%

[Graham Futerfas]

Thanks, Matthew, I’ll try that.

My test with the original settings I mentioned finally rendered, and it looked pretty good. Much better than my 30P originated footage. I used 250%, because 60/24 = 250. Perhaps it’s a simpler way of doing what you suggested above?

I’ll give your method a try and compare.

Thanks!
-Graham

—
Graham Futerfas
Director of Photography
Los Angeles, CA
http://www.GFuterfas.com
—

[Adam Smith]

[Graham Futerfas] “I’d like to create 60 frame slow motion over 24 frame playback, though. I shot both a 60i test and a 30P test…”

Bummer you can’t shoot 60p and convert to 24 like on the 500, but I guess the massive increase in imaging makes up for it! =P

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Video Photographer / Avid & Final Cut Editor