video artifacts in PAL MPEG-2 export using Compressor

[Rafael Amador]

Where are you watching your DVD? If is in the computer screen that’s not a valid refference. You need an interlaced monitor or TV to see if ther is something wrong with the interlacing.
The Compressor setting are correct and enough to make a good MPG2.
But to make a good VDD the first thing you need is a good movie. How do looks your .mov in an interlaced monitor?.
Even if you don’t need to make a QT movie is important that you make some test prior to send to Compressor. When you are happy with your master, then send to Compressor.
You are working with DV and there are few things to do to improve your movie. Before the Nattress G Converter drop the Nattress Nicer or Nattress Chroma Smooth/Sharpening (FC used to have a 411 Chroma Smoothing filter, but I don’t know where is gone). This filter will rebuild the chroma trying to recreate it as was before the DV compression.
Then change your sequence codec to 8 or 10b Uncompress. Render a bit and see (in an interlaced monitor) if your movie looks better.
Cheers,
Rafael

PPC G5 2x2Gh 4GbRAM/BlackMagic SD/PMBP 17″Core2Duo 4GbRAM
JVC DTV-17″/FCS2/AE CS3/COMBUSTION/SHAKE

[Savail]

Thanks so much Rafael, and my apologies for taking so long to reply to your advice.

We were indeed watching this footage on LCD monitors, and finally had a chance to preview it on both a computer CRT monitor and a standard TV broadcast monitor with the same results – the interlace lines were gone.

We also took your advice and did some tests from Compressor in which we compared the same frame of video between a .dv NTSC clip, the same clip converted to PAL .dv (with the Nattress plugin), and an MPEG-2 version of the latter created in Compressor. We found the interlace lines actually appearing following the Nattress PAL conversion, which were of course made worse following the MPEG-2 compression of that converted clip. Why would that be? I thought those lines would have appeared in the original NTSC .dv capture, which is usually interlaced, right?

Furthermore, we actually found that when we simply created a PAL sequence in FCP and rendered our .dv clips to the timeline before exporting as PAL .dv, we got better results across the board – the interlace lines were gone, and did not appear on an LCD monitor nor on a standard TV set. Given that so many people have testified to the Nattress plugin over this cruder method for converting from NTSC to PAL, I am wondering if there is something I am misunderstanding here. Any light you could shed on this would be appreciated.

[Rafael Amador]

Hi Savail,
My suggestion is to try to set your sequence in 8b Uncompress or DV50 at least. Your picture can look much, much better. Make ashort test.
If you have any doubt about the Nattresse filter, please send an e-mail to Graeme. He will answer you really pleased, and size the chance to ask him whatever question you have have.
He really knows.
Rafael

PPC G5 2x2Gh 4GbRAM/BlackMagic SD/PMBP 17″Core2Duo 4GbRAM
JVC DTV-17″/FCS2/AE CS3/COMBUSTION/SHAKE

[Savail]

Rafalaos,

I tested a straight .dv export after applying the Nattress filter and changing the compressor in the sequence settings to both DVCPRO 50 and 8 bit uncompressed, but noticed no difference in quality. If my original captured format is .dv, why would changing the compressor in the sequence settings affect the quality of the image? Shouldn’t I try to match those settings with the source? I will also email Graeme as you suggested about the filter part of this equation.

[Savail]

Rafael,

I tested a straight .dv export after applying the Nattress filter and changing the compressor in the sequence settings to both DVCPRO 50 and 8 bit uncompressed, but noticed no difference in quality. If my original captured format is .dv, why would changing the compressor in the sequence settings affect the quality of the image? Shouldn’t I try to match those settings with the source? I will also email Graeme as you suggested about the filter part of this equation.