Why 24p? at DVinfo.net

Andy Tejral · April 22nd, 2008, 04:32 PM

Personally I think this looks like doo-doo. http://vimeo.com/929466

Now, I didn't do anything to extract the 24p. I just sucked it into Edius as an HQ avi (which I believe is similar in nature to Cineform), trimmed it and exported it as quicktime h.264 at 24p.

I think the frame artifacting is horrible.

Eugenia Loli-Queru · April 22nd, 2008, 07:42 PM

This is to be expected if you didn't remove pulldown. If you were only going to watch these videos on a TV, it's ok to not remove pulldown, but for the PC and the web, or for iPods, you might need to do the extra work. Your other videos look similar too, there is some ghosting, e.g. the video with the dog.

Andy Tejral · April 22nd, 2008, 08:14 PM

Well, in fact, the Aurora Summit video (actually the moon one) is the first time I turned the PF24 mode on.

I think the interlacing artifacts are just part of the fast action of the dog and the HDV compression. Everything before the Aurora Summit video was shot in regular 60i.

Diving into Edius, I see two capture presets: 2-3-2-3 or 2-3-3-2. The first is described as Sony/Canon and the second Canon. I'll do some experimenting but does anyone know which is more appropriate?

Eugenia Loli-Queru · April 22nd, 2008, 08:22 PM

These are not interlacing artifacts I saw on your dog video. It was heavy ghosting. It seems that you might not be editing or exporting properly, or your editor heavily resamples and adds motion blur. You might need to tell your editor to not do that... I know that on Sony Vegas on many fast scenes I have to disable resample to avoid ghosting. Might be similar on Edius? Maybe a way to force Edius to not motion blur is to export at 29.97 frame rate and not 30.00? I downloaded your video you see, and you had exported at 30 sharp, which is not the right NTSC frame rate. Maybe this small change forces Edius to resample heavily.

David Newman · April 22nd, 2008, 09:14 PM

The pulldown removal would have been a good starting point, exporting 24p from 60i source (with 24p embedded) is going to frame blend to generate psuedo 24p. If you are lucky is might guess the original 24p cadence and it won't look too bad for some edits (20% probability), but you weren't lucky, as a result you have two frames blended into one - that is why the double image (it is like 3D without the glasses.) 24p extracted well, and posted as 24p (23.976p) looks very nice, but the camera doesn't make this easy. If you want to edit like you describe, shoot 60i with a 1/60th shutter, then the pseudo 24p exports will be OK -- although not as good as correctly captured and posted 24p.

April 22nd, 2008, 04:32 PM	#1
Andy Tejral Major Player Join Date: Jan 2007 Location: New York City Posts: 523	Why 24p? Personally I think this looks like doo-doo. http://vimeo.com/929466 Now, I didn't do anything to extract the 24p. I just sucked it into Edius as an HQ avi (which I believe is similar in nature to Cineform), trimmed it and exported it as quicktime h.264 at 24p. I think the frame artifacting is horrible. __________________ Andy Tejral Railroad Videographer

April 22nd, 2008, 08:14 PM	#3
Andy Tejral Major Player Join Date: Jan 2007 Location: New York City Posts: 523	Well, in fact, the Aurora Summit video (actually the moon one) is the first time I turned the PF24 mode on. I think the interlacing artifacts are just part of the fast action of the dog and the HDV compression. Everything before the Aurora Summit video was shot in regular 60i. Diving into Edius, I see two capture presets: 2-3-2-3 or 2-3-3-2. The first is described as Sony/Canon and the second Canon. I'll do some experimenting but does anyone know which is more appropriate? __________________ Andy Tejral Railroad Videographer Last edited by Andy Tejral; April 22nd, 2008 at 10:44 PM.

April 22nd, 2008, 09:14 PM	#5
David Newman CTO, CineForm Inc. Join Date: Jul 2003 Location: Cardiff-by-the-Sea, California Posts: 8,095	The pulldown removal would have been a good starting point, exporting 24p from 60i source (with 24p embedded) is going to frame blend to generate psuedo 24p. If you are lucky is might guess the original 24p cadence and it won't look too bad for some edits (20% probability), but you weren't lucky, as a result you have two frames blended into one - that is why the double image (it is like 3D without the glasses.) 24p extracted well, and posted as 24p (23.976p) looks very nice, but the camera doesn't make this easy. If you want to edit like you describe, shoot 60i with a 1/60th shutter, then the pseudo 24p exports will be OK -- although not as good as correctly captured and posted 24p. __________________ David Newman -- web: www.gopro.com blog: cineform.blogspot.com -- twitter: twitter.com/David_Newman

April 22nd, 2008, 07:42 PM	#2
Eugenia Loli-Queru Major Player Join Date: Jun 2007 Location: Bay Area, CA, USA Posts: 348	This is to be expected if you didn't remove pulldown. If you were only going to watch these videos on a TV, it's ok to not remove pulldown, but for the PC and the web, or for iPods, you might need to do the extra work. Your other videos look similar too, there is some ghosting, e.g. the video with the dog.

April 22nd, 2008, 08:22 PM	#4
Eugenia Loli-Queru Major Player Join Date: Jun 2007 Location: Bay Area, CA, USA Posts: 348	These are not interlacing artifacts I saw on your dog video. It was heavy ghosting. It seems that you might not be editing or exporting properly, or your editor heavily resamples and adds motion blur. You might need to tell your editor to not do that... I know that on Sony Vegas on many fast scenes I have to disable resample to avoid ghosting. Might be similar on Edius? Maybe a way to force Edius to not motion blur is to export at 29.97 frame rate and not 30.00? I downloaded your video you see, and you had exported at 30 sharp, which is not the right NTSC frame rate. Maybe this small change forces Edius to resample heavily.