top field, bottom field or non-interlaced? at DVinfo.net

Graham Jones · November 8th, 2005, 01:53 AM

I'm burning 25p footage onto a DVD with Sonic DVDit 6.

It doesn't seem to matter whether I choose top field, bottom field or non-interlaced - the quality is very good. I'm obviously inclined to select non-interlaced as my footage is progressive.

Then again, I'm watching it on a computer monitor and the DVD will be watched on TV screens with standalone DVD players.

What setting is the wisest?

Thanks in advance.

Dan Euritt · November 8th, 2005, 01:56 PM

you should not use a computer to make the final decision about any aspect of ntsc video.

i would encode it just like it was shot, if at all possible.

James Llewellyn · November 8th, 2005, 02:21 PM

For dvd, you should use either Bottom Field or Non-Interlace, and yeah don't base your judgment on how you view it on your pc. DVD playing software on pc's like WinDVD or PowerDVD tends to use filters on the footage such as bob and weave to deal with the interlacing on most dvd's during playback, and affects the quality some.

EDIT: I was wrong and you should use Bottom Field, I had previously said Top Field but I was thinking about most movie DVDs (most of which are Top Field).

Graham Jones · November 10th, 2005, 12:08 PM

Ah.... everything I do is tested subsequently on a standalone guys. However sitting here doing my first encode attempt I was just wondering whether there was a best practice for 25.00 Progressive --> DVD in terms of field setting.

Non interlaced, sound like.

Dan Euritt · November 10th, 2005, 05:34 PM

as i understand mpeg2 encoding for dvd, even if it's encoded progressive, it'll still get split into fields during playback, then recombined back into a progressive frame... i'm guessing that's why you should maybe go with the best quality option, which is to encode it just how it was shot(??).

top field first vs. bottom field first is a whole lot more confusing... both pal and ntsc dv use the latter, but most other video is shot with top field first, so it ends up as top field first, like james said... and there are a lot of people who believe that if your encoder is up to it, you should convert bff to tff... i'm sticking with the way it was shot(bff), because i've never had a compatibility issue from that.

Joshua Provost · November 11th, 2005, 12:04 AM

Graham,

Is your footage true 25p? If so, you should instruct your NLE and DVD encoder/authoring that it is "progressive" or "no fields." MPEG-2 encodes progressive and interlaced in a different manner, so it will effect the footage, if even in a small way.

Josh

Matt Brabender · November 11th, 2005, 03:28 PM

Same as these guys - I was under the impression that for the best quality, match what you shoot.
But I also thought that if you do go interlaced, then the field order only matters if source image is interlaced. Meaning you can choose either top or bottom field first without any jitter as you're not swapping the field order, you're creating it.

November 8th, 2005, 01:53 AM	#1
Graham Jones Major Player Join Date: Jan 2004 Location: Europe Posts: 489	top field, bottom field or non-interlaced? I'm burning 25p footage onto a DVD with Sonic DVDit 6. It doesn't seem to matter whether I choose top field, bottom field or non-interlaced - the quality is very good. I'm obviously inclined to select non-interlaced as my footage is progressive. Then again, I'm watching it on a computer monitor and the DVD will be watched on TV screens with standalone DVD players. What setting is the wisest? Thanks in advance. __________________ www.irishfilmmaker.com

November 8th, 2005, 02:21 PM	#3
James Llewellyn Regular Crew Join Date: Nov 2005 Posts: 80	For dvd, you should use either Bottom Field or Non-Interlace, and yeah don't base your judgment on how you view it on your pc. DVD playing software on pc's like WinDVD or PowerDVD tends to use filters on the footage such as bob and weave to deal with the interlacing on most dvd's during playback, and affects the quality some. EDIT: I was wrong and you should use Bottom Field, I had previously said Top Field but I was thinking about most movie DVDs (most of which are Top Field). Last edited by James Llewellyn; November 8th, 2005 at 06:31 PM.

November 10th, 2005, 12:08 PM	#4
Graham Jones Major Player Join Date: Jan 2004 Location: Europe Posts: 489	Ah.... everything I do is tested subsequently on a standalone guys. However sitting here doing my first encode attempt I was just wondering whether there was a best practice for 25.00 Progressive --> DVD in terms of field setting. Non interlaced, sound like. __________________ www.irishfilmmaker.com

November 11th, 2005, 12:04 AM	#6
Joshua Provost Major Player Join Date: Sep 2004 Location: Phoenix, AZ Posts: 493	Graham, Is your footage true 25p? If so, you should instruct your NLE and DVD encoder/authoring that it is "progressive" or "no fields." MPEG-2 encodes progressive and interlaced in a different manner, so it will effect the footage, if even in a small way. Josh __________________ Owner/Operator, 727 Records Co-Founder, Matter of Chance Productions Blogger, Try Avoidance

November 8th, 2005, 01:56 PM	#2
Dan Euritt Trustee Join Date: Mar 2004 Location: Carlsbad CA Posts: 1,132	you should not use a computer to make the final decision about any aspect of ntsc video. i would encode it just like it was shot, if at all possible.

November 10th, 2005, 05:34 PM	#5
Dan Euritt Trustee Join Date: Mar 2004 Location: Carlsbad CA Posts: 1,132	as i understand mpeg2 encoding for dvd, even if it's encoded progressive, it'll still get split into fields during playback, then recombined back into a progressive frame... i'm guessing that's why you should maybe go with the best quality option, which is to encode it just how it was shot(??). top field first vs. bottom field first is a whole lot more confusing... both pal and ntsc dv use the latter, but most other video is shot with top field first, so it ends up as top field first, like james said... and there are a lot of people who believe that if your encoder is up to it, you should convert bff to tff... i'm sticking with the way it was shot(bff), because i've never had a compatibility issue from that.

November 11th, 2005, 03:28 PM	#7
Matt Brabender Major Player Join Date: Jul 2005 Posts: 230	Same as these guys - I was under the impression that for the best quality, match what you shoot. But I also thought that if you do go interlaced, then the field order only matters if source image is interlaced. Meaning you can choose either top or bottom field first without any jitter as you're not swapping the field order, you're creating it.