View Full Version : Cinema Tools--- "Conform" vs "Reverse Telecine"


Matt Irwin
December 6th, 2006, 06:14 PM
I want to use some 60i DV footage (telecined film dailies) in a 23.98 sequence.

I have not used Cinema Tools before, so I wanted to check...
If I'm converting 60i/29.97 to 23.98, what is the difference between "Conform" and "Reverse Telecine?" Both give the option to change the frame rate and both (to my eye) produce the same motion from the clips.
Is there any prep work I need to do to the footage before converting in Cinema Tools?

Mike Schrengohst
December 6th, 2006, 11:51 PM
23.98 is progressive....
So you need to de-interlace the 60i clip first.....
I recommend the Nattress filters for de-interlacing.
http://www.nattress.com/Products/filmeffects/filmeffects.htm
Then take your 29.97 de-interlaced file and conform to 23.98
Reverse TeleCine does just that. 24p footage (not 24pA or 24pN footage)
is really 29.97 with a pulldown added. So when you reverse telecine your 24p footage really becomes 24p (confusing I know) that you can use in a 23.98 sequence.

Nate Weaver
December 7th, 2006, 12:13 AM
Mike, deinterlacing telecined film at 29.97 is going to mix fields from 2 different film frames at times in the cadence. That's bad.

Matt, the difference between conforming and reverse telecine is...

Conform: In this context, it's taking a clip that plays at X-fps and telling Quicktime it needs to play it at Y-fps. It doesn't change the picture data itself, it just changes the header of the Quicktime file so it plays at a new speed. Make sense?

Reverse telecine: Remove the redundant fields in a 29.97 video clip of 24p material, like what you have from your telecine session, and gives you your 24p material in a Quicktime file that has only 23.98 frames per second and no more.

The trick is is that you either need to know what the cadence is of your video from the telecine, so Cinema Tools can go to work on it right...or be prepared to try each of the 5 possibilities on a trial and error basis.

Matt Irwin
December 7th, 2006, 12:19 AM
Great answers! I understand perfectly now. Thanks both of you.