PAL to NTSC footage conversion - need your advice

[Peter Sieben]

I have to finish a short movie within two weeks to send it over to the United States for a filmfestival/contest. Despite of earlier info of the festival, I only am allowed to send in an NTSC-dvd and not a PAL-dvd.

As I live in Europe, I have to convert my footage. The footage was shot with a DVX100 PAL camera, using the 25P (progressive) mode and widescreen (black bars). I understand that Vegas 4 (my NLE) can do the conversion for me. Please I would like to know:
1) what the best Vegas settings are to convert PAL to NTSC?
2) is there anything special on the NTSC DVX100 features in Vegas that I can use to enhance this conversion?
3) Would a PAL resolution blow up of the size of the video before I render to NTSC help to have a more accurate conversion?

Many thanks,
Peter

[Glen Elliott]

I'm particularly interested in the answer to this question as well. As I soon have to do something similar. I'm editing PAL footage for a friend but needs to be output to a NTSC compatable DVD.

Do I simply edit in Vegas under a PAL template then when I go to output the MPG2 choose the NTSC preset?

Will that handle all the changes that have to be made (ie Resolution and frame rate)?

Stretching it to 720x480 will give it a slight widened look correct?....any way around that?

How about frame rate- it's going to interpolate the extra 5 frames? Will this have a *noticable* negative affect on video quality?


Thanks inadvance!

[Rob Lohman]

I haven't tested it out, but it isn't as simple as a stretch (shrink
is actually the better word here) since you need to change the
pixel aspect ratio. BUT, the good news is (according to a quick
calculation on my part) that if you resize to 720x480 and export
that as 720x480 @ 0.9 pixel aspect you should be okay, why?

1.067 / (576 / 480) = 0.9 (roughly)

[Glen Elliott]

Rob I tried rendering some PAL footage out as WMV (which doesn't have a PAL template) so it took on the default NTSC attributes. The clips play fine but look a bit squashed vertically.

So simply rendering PAL footage out using an NTSC template isn't recommended? Say if I have PAL footage I'm editing in a PAL timeline- then want to make an NTSC DVD. What *exact* steps should I take?

Is there a way to maintain the dimensions and not "squash" the video in any direction even if it means cropping somehow?




*Sorry Pete, don't mean to take over your post- I figured we are both trying similar things and my questions might lead to answers for you as well*

[Rob Lohman]

I'll see if I can run some tests. At this moment my harddisk with
all my footage on it has just failed.....

[Peter Sieben]

Hi Rob and Glen,

I look forward to your tests. I did some small tests today with a five seconds clip from my current project. For rendering I used the DV NTSC and also the DV NTSC 24P-version presets. One of them didn't work, the others gave a reasonable quality, but one way or another it was like there was some kind of shadow/delay that was "behind" movements on the screen. I couldn't test it properly and only checked it via Windows Media Player.
I took 2 screenshots from the rendered files (via Power-DVD which gave strange aspect ratio's which I corrected a bit via Photo Editor). The NTSC footage looks a bit softer, but that could be caused by the fact that I grapped a different frame from the footage. Check them at www.orphic.nl/odm/pal2ntsc.jpg.

Looking forward to your suggestions!

Peter

[Glen Elliott]

See the NTSC looks squished (ie girls face looks fatter). It's obviously due to the resolution discrepency between PAL and NTSC....I'm wondering if there is a way around this- to convert it without the improper proportunes.

[Peter Sieben]

Glen, I did frame grabs with Power DVD and some way or another it sometimes gives strange aspect ratios on my pc (also with commercial dvd's), so don't judge the pictures on their sizes. It's more the softness that worries me looking at the NTSC picture.

[Glen Elliott]

The softness is most definitly due to interopolating to match the NTSC resolution and frame rate. It's gotta shrink it's height and *add* 5 fps to be converted to NTSC.

[Peter Sieben]

Hi Rob and Glen,

Any suggestions about the best Vegas settings for PAL to NTSC conversion?

Thanx,

Peter

[Glen Elliott]

Seems theres no definitive answer thus so far. No matter which way you do it your going to lose quality simply because of the difference in resolution and frame rate. It's gotta shrink it's verticle resolution to match NTSC which will cause a slight squishing. It's also got to add 5 frames a second to bring it from 25fps to 29.97. Just like image editing- any time you try and "add" information that isn't there (ie Frames in this instance) your going to see quality loss due to interopolation.

[Rob Lohman]

I did a small test and to me it looked good with the correct
aspect ratio for NTSC. What I did was the following: I set Vegas
to an NTSC project and loaded my PAL footage. I then exported
an NTSC DV AVI file from Vegas with the Render As option.

Both the pixel aspect and frame rate looked fined to me.

[Glen Elliott]

Rob when you do that it *does* automatically change the PAL res to the NTSC standard as soon as you drop your footage on the timeline. There is, however, a squeeze done- try it by taking a still from the PAL footage in the NTSC timeline and one from the PAL timeline. NTSC is shorter (vertical resolution less) than PAL.

[Rob Lohman]

I looked at a circle and it looked fine, if I have a chance I'll put
up some screengrabs later.

[Peter Sieben]

Hi Rob and Glen,

I'll do a test like Rob did.
Still a question that's unanswered: the 25P footage of the DVX100, has that any advantage in combination with the special DVX100 NTSC pulldown render templates within Vegas?

Peter