some questions about reverse telecine

[dv416]

ive read the sticky's, and researched online. i knwo HOW to reverse telecine, but i still dont understnad the process well enough. so... a few quesitons...

1. compressor. it auto-detects the cadence of 24p footage right? so that IVTC after the edit is totally reliable?

2. the gh1 1080p/24 is in the 60i container at a 3:2 pulldown, right? so, reverse telecine returns it to 23.976, as scanned by the sensor...

3. what are the downsides to reverse telecine over say pulldown removal from 24pa? is it that reverse telecine is deinterlacing the mixed frames instead of dropping them altogether? so you'd technically have one slightly muddier frame every few frames? hard to tell from gh1 1080 footage i just IVTC'd, so it makes me wonder.

4. also... the mud from movement on the pre-hack gh1 1080 is NOT IVTC related, correct? it is the result of the camera's internal processing? the missing b-frame thing? can someone explain that for me? or link me to something that does? its hard to find anything "mud" related now unless its about the hack. i just want to understand the original problem better.

thanks!

 

[svecher]

1. compressor. it auto-detects the cadence of 24p footage right? so that IVTC after the edit is totally reliable?

Don't know much about Macs, but AFAIK FCP is not telecine-aware, i.e. you need to reverse 2:3 pulldown via third party software before log and transfer for best results.

2. the gh1 1080p/24 is in the 60i container at a 3:2 pulldown, right? so, reverse telecine returns it to 23.976, as scanned by the sensor...

Correct, although when analyzing native sensor output enabled through PTools the resultant frame rate is actually 23.971 fps.

3. what are the downsides to reverse telecine over say pulldown removal from 24pa?

AFAIK, those two names refer to one and the same process. When applied to 24PsF (60 interlaced frames) footage the duplicated fields are removed and the result is 24 progressive frames. This is opposed to "regular" deinterlacing which will produce 30 progressive frames.

 

[dv416]

i read that copressor auto detects 3:2 cadence for IVTC from someone else on this forum. just wanted to confirm. i know about the 23.971 thing, apparently that is related to the labeling of the fields (it comes in as upper when it should be none) and is not a problem when imported.

24pa is a 2:3:3:2 cadence. reverse telecine is done for footage at 3:2. definitely not the same.