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HD NTSC to PAL Debacle

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Carlo Mirabella-Davis
HD NTSC to PAL Debacle
on Oct 28, 2008 at 4:41:38 pm

Dear Compression sages,

I'm attempting to convert my NTSC DVCpro HD 720 Quicktime to PAL to make a PAL DVD in DVDSP. So I need a PAL mpeg2. My trouble starts here.

In Apple's Compression program I followed all the settings to convert to PAL. The resulting mpeg was a little rough in terms of quality, but it was the best I could get it. It seemed to play alright.

But to my horror when I dropped the clip into the DVDSP timeline I discovered that all the subtitles I had made in my NTSC DVDSP project gradually went out of sync. The DVDSP project had been fully converted to PAL, every menu. But this gradual de-syncing of the subtitles confused me. And this is not the kind of project that I can easily move the subtitles over. 26 min, heavy on the lines, 5 subtitle tracks.

I checked the audio sync and it seemed to be in sync, but I couldn't be clinically certain frames weren't being dropped towards the end. I did some research and discovered that many people had been having trouble with conversions from NTSC to PAL. Out of sync audio issues, frames being dropped, etc.

In desperation I consulted a friend, who recommended I use a FCP plug-in to do the conversion called Nattress Standards Conversion. He said he had had frame dropping issues with other transfers, but that the NSD plug-in had worked great.

I downloaded the plug-in, and attempted to follow the instructions (bellow) only to find that on step 9, it did not recognize the proper aspect ratio of my HD footage, giving me 4:3 instead of 6:9. I tried switching a few settings, but to no avail. Everytime I dragged and dropped the origional source clip into the filter interface the clip in the viewer altered to 4:3 ratio. Blast, I thought. Probably some little setting I will never discover.

So here I am, back on the compression forums. Has anyone successfully used compressor to convert NTSC HD to PAL without getting drop frames or subtitles gradually going out of sync? How on earth do I do this conversion without shoddy results?

----------

NTSC to PAL conversion for Nattress:

1. edit the NTSC clip to an PAL timeline

2. nest the NTSC clip to allow the plugin to scale the converted clip. Because the pixel
dimensions of NTSC video are smaller than PAL, the clip will appear shrunk down in
the timeline canvas viewer. This is normal. The nesting of the clip will allow the
plugin to correctly scale it to PAL pixel dimensions. (select clip and go to the Se-
quence Menu and select Nest Items - make sure the pixels dimensions of the nest
are PAL sized)

3. apply the G Converter plugin to the nested sequence in the PAL timeline. Make sure
the plugin goes onto the nest itself, not the clip that it contains.

4. open the nest in the viewer (control click on the nest and select "Open in viewer" or
select nest then press return)

5. select the filter tab in the viewer

6. set the correct settings for the desired conversion. In this case, we select Source
Pixel size to be 720 x 480 (NTSC), lower field order for source (in this case a NTSC
DV clip) and destination (PAL DV timeline).

7. if you desire the PAL output to be de-interlaced, this can be performed in one step by
selecting progressive output

8. if you would like to experiment with the conversion algorithm using "Smart De-
Interlacing" then this can be selected in the De-Interlace options. The Tolerance
control affects the smart de-interlace and it's effects can be seen by selecting "View
Smart Mask" in the De-Interlace Options.

9. the original NTSC clip that was edited to the PAL timeline must now be dropped from
the project browser onto the Source Clip image well in the filter. The plugin will use
this video clip for all the image data for the conversion. This is the important step
that makes this plugin different from any other, and is vital to it's successful operation.


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Daniel Low
Re: HD NTSC to PAL Debacle
on Oct 28, 2008 at 8:40:06 pm

Just to be pedantic, there is no such thing as 'NTSC HD', in the same way as there's not such thing as PAL HD, HD is referred to by vertical frame size along with frame rate and whether it's interlaced or progressive, so 'NTSC DVCPro 720' should actually be '720p 30' (or 29.97).

So you are attempting to go from '720p 30' to '576i 25'

The reason your subtitles are drifting is because you are removing roughly 5 frames per second.

To be perfectly honest, I rate the Nattress plug-in very highly, but the only way you'll get this done properly, without shoddy results, is to use the services of a professional, broadcast quality, standards converter.




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Carlo Mirabella-Davis
Re: HD NTSC to PAL Debacle
on Oct 28, 2008 at 9:38:24 pm

Ahhh I see. Thank you very much for responding. So if you DO rate the Nattress plug-in highly, perhaps you can guide me in how to use it correctly. What am I doing wrong with Nattress? Why is the aspect ratio all messed up?

And what profession convertor would you suggest? So many studios here in NYC just use the same programs I have.



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Carlo Mirabella-Davis
Re: HD NTSC to PAL Debacle
on Oct 28, 2008 at 9:47:20 pm

And let me ask you this as well, will I always be loosing 5 frames per second with any NTSC to PAL transfer I do, professional or not? Or am I loosing frames because it's a shoddy transfer? Will Nattress solve that issue? And if I am ALWAYS going to be loosing 5 frames a second, how do I solve the subtitle issue? Thanks for the help.





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Daniel Low
Re: HD NTSC to PAL Debacle
on Oct 28, 2008 at 10:48:07 pm

You are not exactly loosing the frames, rather interpolating them from 29.97 to 25.

http://en.wikipedia.org/wiki/Telecine

http://www.macworld.com/article/49306/2006/02/marchcreate.html


Google for more.

__________________________________________________________________
Please post back saying what solved your problem. It could help others, and saying 'thanks' is free!


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Daniel Low
Re: HD NTSC to PAL Debacle
on Oct 28, 2008 at 10:33:05 pm

I rate the Nattress plug-in for doing SD standards conversion, not HD to SD. In this instance I suggest that you contact Mr Nattress himself for help and advice, you paid for his product and part of that should include a certain level of support.

A professional Standards converter would very likely have the words 'Snell & Wilcox' on the front:

http://www.snellwilcox.com/products/conversion_restoration/products.php




__________________________________________________________________
Please post back saying what solved your problem. It could help others, and saying 'thanks' is free!


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