Duplicate frames. Please help? at DVinfo.net

Ryan Mueller · March 4th, 2008, 12:36 PM

I am working in a 23.98 timline with footage from an XL2 and an HV20. The XL2 footage that I reverse telecined in cinema tools looks fantastic in the timeline, the HV20 footage that I rev. tele. in compressor has duplicate frames. They appear to be very random but on average I'd say that they appear every 84-85 frames. It also appears that there may be some missing frames.

When I reverse telecined the footage in compressor, I used a frame rate of 23.976. Could this be the culprit? Should I have just rounded it up to 23.98?

Please help!

Ryan

Neil Rostance · March 4th, 2008, 03:29 PM

I'm a little confused about this reverse telecine thing. Do you mean capture/export?

Ryan Mueller · March 4th, 2008, 04:24 PM

Not capture or export. When working with footage that is shot in 24P the camera actually records 29.97 interlaced with a 2:3:2:3 pulldown (non advanced). To remove this pulldown so that the end result is 24 or 23.98 progressive fps, you must go through a process that is called reverse telecine.

Mike Barber · March 4th, 2008, 04:54 PM

Quote:

Originally Posted by Ryan Mueller

footage that is shot in 24P the camera actually records 29.97 interlaced with a 2:3:2:3 pulldown

For clarity sake, we should note that some cameras do this, not all. It is important to be aware of whether the camera you are using uses pulldown (and what kind) or not.

Quote:

Originally Posted by Ryan Mueller

To remove this pulldown so that the end result is 24 or 23.98 progressive fps, you must go through a process that is called reverse telecine.

For Advanced pulldown (2:3:3:2), reverse telecine is not required. There are two other options, which are much less of a headache: removing pulldown while capturing, or removing after the fact via the Remove Advanced Pulldown command under the Tools menu.

However, Ryan specified he has footage that is using the non-advanced pulldown...

Ryan Mueller · March 4th, 2008, 07:13 PM

Thank you Mike, you are correct in all areas. My major problem is that the pulldown is not flagged by the camera. This has made it very difficult to rev. telecine. If anybody knows how to rev. telecine un-flagged 24P 2:3:2:3 footage, I would be eternally grateful.

March 4th, 2008, 12:36 PM	#1
Ryan Mueller Major Player Join Date: Mar 2007 Location: Highlands Ranch, CO Posts: 336	Duplicate frames. Please help? I am working in a 23.98 timline with footage from an XL2 and an HV20. The XL2 footage that I reverse telecined in cinema tools looks fantastic in the timeline, the HV20 footage that I rev. tele. in compressor has duplicate frames. They appear to be very random but on average I'd say that they appear every 84-85 frames. It also appears that there may be some missing frames. When I reverse telecined the footage in compressor, I used a frame rate of 23.976. Could this be the culprit? Should I have just rounded it up to 23.98? Please help! Ryan

March 4th, 2008, 03:29 PM	#2
Neil Rostance Regular Crew Join Date: Nov 2006 Location: Lace Market, Nottingham, UK Posts: 194	I'm a little confused about this reverse telecine thing. Do you mean capture/export?

March 4th, 2008, 04:24 PM	#3
Ryan Mueller Major Player Join Date: Mar 2007 Location: Highlands Ranch, CO Posts: 336	Not capture or export. When working with footage that is shot in 24P the camera actually records 29.97 interlaced with a 2:3:2:3 pulldown (non advanced). To remove this pulldown so that the end result is 24 or 23.98 progressive fps, you must go through a process that is called reverse telecine.

March 4th, 2008, 07:13 PM	#5
Ryan Mueller Major Player Join Date: Mar 2007 Location: Highlands Ranch, CO Posts: 336	Thank you Mike, you are correct in all areas. My major problem is that the pulldown is not flagged by the camera. This has made it very difficult to rev. telecine. If anybody knows how to rev. telecine un-flagged 24P 2:3:2:3 footage, I would be eternally grateful.