Standard Pulldown Causes and Error Every Third Frame? at DVinfo.net

Peter Moretti · January 27th, 2008, 05:51 AM

DVFilm recommends using an advanced pulldown (2:3:3:2) instead of a standard pulldown (3:2) for footage that will be converted to a 24 frame timeline.

They say when doing pulldown removal on a standard 3:2 pulldown, every 3rd frame will be distorted.

http://dvfilm.com/maker/why24PA.htm

"When to shoot 24p? 24p Advanced? 30p?" also explains the issue:

http://www.adamwilt.com/24p/index.html#TOC

Has anyone run into this issue with the HV-20?

Tom Alexander · January 27th, 2008, 08:55 PM

Hmm, I haven't. I have been doing standard 3:2 pulldown and have checked frame by frame and it looks fine. I will read the artice (I'm at work and can't at the moment)

Robert Ducon · January 28th, 2008, 03:05 AM

Interesting article.

Made me think about it, and while it makes sense as it's just regular ole MPEG compression at work, I don't think it's an issue, or if it is, I haven't seen any signs.

Why?

Well, if you think about it, shooting at a BLANK evenly lit, evenly coloured area like a wall, or the sky or what have you, then you'd expect to see every 3rd frame's colour change slightly from the one before it, and the one after it.

At a frame rate of twenty-four frames a second, 8 frames would be altered and thus, you'd see a flicker.

I've seen regular camera noise in my 1080P 24P footage, same as any camera footage, but I've seen no unexplainable flicker.

Peter Moretti · January 28th, 2008, 03:20 AM

Robert,

When you shoot 24P and capture out of the HDMI port, does the camera add a pulldown and use a 60i timeline, or does it just spit out 24 progressive frames every second?

Thanks much.

Robert Ducon · January 29th, 2008, 01:02 AM

HD-SDI always uses 60i as a transfer hertz, so it's 24P in a 60i timeline that needed me to reverse telecine in another process.

Cineform touts being able to do it all in real time, would sounds great, but it's not been an option on the Mac - certainly wasn't at the time of the job.

Apple Compressor simply would NOT inverse-telecine the footage I captured from the HV20 in Apple ProRes 422. It'd crash, and crash, and crash. So I have to inverse telecine everything in AE 7 - which looks great, just takes a long time. It was all worth it in the end!

January 27th, 2008, 05:51 AM	#1
Peter Moretti Trustee Join Date: Mar 2007 Location: Sherman Oaks, CA Posts: 1,259	Standard Pulldown Causes an Error Every Third Frame? DVFilm recommends using an advanced pulldown (2:3:3:2) instead of a standard pulldown (3:2) for footage that will be converted to a 24 frame timeline. They say when doing pulldown removal on a standard 3:2 pulldown, every 3rd frame will be distorted. http://dvfilm.com/maker/why24PA.htm "When to shoot 24p? 24p Advanced? 30p?" also explains the issue: http://www.adamwilt.com/24p/index.html#TOC Has anyone run into this issue with the HV-20? Last edited by Peter Moretti; January 27th, 2008 at 04:32 PM.

January 28th, 2008, 03:05 AM	#3
Robert Ducon Major Player Join Date: Nov 2006 Location: Victoria BC Posts: 400	Interesting article. Made me think about it, and while it makes sense as it's just regular ole MPEG compression at work, I don't think it's an issue, or if it is, I haven't seen any signs. Why? Well, if you think about it, shooting at a BLANK evenly lit, evenly coloured area like a wall, or the sky or what have you, then you'd expect to see every 3rd frame's colour change slightly from the one before it, and the one after it. At a frame rate of twenty-four frames a second, 8 frames would be altered and thus, you'd see a flicker. I've seen regular camera noise in my 1080P 24P footage, same as any camera footage, but I've seen no unexplainable flicker. __________________ Mac + Canon HV20

January 29th, 2008, 01:02 AM	#5
Robert Ducon Major Player Join Date: Nov 2006 Location: Victoria BC Posts: 400	HD-SDI always uses 60i as a transfer hertz, so it's 24P in a 60i timeline that needed me to reverse telecine in another process. Cineform touts being able to do it all in real time, would sounds great, but it's not been an option on the Mac - certainly wasn't at the time of the job. Apple Compressor simply would NOT inverse-telecine the footage I captured from the HV20 in Apple ProRes 422. It'd crash, and crash, and crash. So I have to inverse telecine everything in AE 7 - which looks great, just takes a long time. It was all worth it in the end! __________________ Mac + Canon HV20

January 27th, 2008, 08:55 PM	#2
Tom Alexander Regular Crew Join Date: May 2007 Location: Ontario, Ca. Posts: 121	Hmm, I haven't. I have been doing standard 3:2 pulldown and have checked frame by frame and it looks fine. I will read the artice (I'm at work and can't at the moment)

January 28th, 2008, 03:20 AM	#4
Peter Moretti Trustee Join Date: Mar 2007 Location: Sherman Oaks, CA Posts: 1,259	Robert, When you shoot 24P and capture out of the HDMI port, does the camera add a pulldown and use a 60i timeline, or does it just spit out 24 progressive frames every second? Thanks much.