View Full Version : PAL to NTSC converter for XL1s?


Didi Schoeman
September 24th, 2003, 05:44 AM
I know this has been asked a million times, but I cant seem to find an answer on any of the discussions that seems to give me the answer I’m looking for.

I’m shooting and editing all my productions in PAL, and then distribute my masters on mini DV. Now the million-dollar question, does anybody know of a fire wire system that would be able to convert a digital PAL signal into a digital NTSC signal without losing quality or sync?

I know you get Analogue systems that take the signal from RCA connectors, but my head is telling me that if I use my XL1s as a player and use the RCA connectors on the back, wire it trough the converter into a NTSC DV recorder via its RCA connector inputs, that there will be a pretty big quality loss because the signal goes from DIGITAL to ANALOG back to DIGITAL. (And I am not sure weather the analogue output on the XL1s is of high enough quality.)

How do the video houses do it? At the moment I have to send my masters off to Johannesburg which is about 500km from where I live and have it converted over there which is costing an arm and a leg, hoping that I can save myself time and money in the long run by installing a system that would enable me to do it myself.

Of course the other option would be to do it in post on our computers. We use Final Cut Pro on a Mac G4 system. I’ve tried to convert my programs in FCP and Quick Time, but the quality is horrendous and not of broadcast quality.

I suppose my question is: Does anyone know of a Digital converter that would kick out the quality needed for broadcast, or maybe even a software program that would be able to do it on a Mac without sacrificing any quality or sync?

Any help or advice would be greatly appreciated!

Regards

Juan P. Pertierra
September 24th, 2003, 09:28 AM
I think the answer to your question is no, not do miniDV anyways. miniDV tapes in NTSC do 4:1:1 quantizing while in PAL they do 4:2:0. If you record something in miniDV in PAL and then dub it to an NTSC miniDV tape, you will get the worst of both worlds, something like 4:1:0 which is probably why it looks horrendous.

What I would do is to find access to a Betacam or prefferably digiBeta deck and dub it to that. It's a professional standard anyways so everyone is bound to have it, and since it does 4:2:2, you should not loose the color information. Only other way I can think of is to leave it in a computer format upon capture.

I might be wrong, i've never actually done this. Someone correct me.

Cheers,
Juan

Frank Granovski
September 24th, 2003, 09:54 AM
The best way is to shoot/edit in NTSC as well. If your market is only NTSC, then shoot only NTSC. For some of my instructional videos I did years ago, we used 2 cameras at the same time, one PAL, the other NTSC.

Jeff Donald
September 24th, 2003, 10:05 AM
There are no modestly priced standards convertors that do a good job. I would get the finished project converted professionally at a post house. Software conversions never look good enough for broadcast, to my eye.

Juan P. Pertierra
September 24th, 2003, 10:20 AM
Jeff,

Would dubbing a PAL miniDV tape directly to digiBeta work? It should loose any color info right? Except for the recompression...

Jeff Donald
September 24th, 2003, 10:48 AM
What standard digibeta?

Juan P. Pertierra
September 24th, 2003, 10:59 AM
i'm not sure as I haven't physically used them, but I know Sony's Digital Betacam uses 4:2:2 and either 3.3:1 or 2:1 compression(?)

but yeah i forgot about the frame rate issue...i guess you could load it up into a computer that uses 4:2:2, adjust resolution/pixel aspect ratio/frame rate somehow, and then record that onto NTSC digital betacam, and you could keep the colors as they are.

Otherwise, if you wanted to copy to NTSC miniDV, you'd have to still do all this, plus find a way to retain the color information from 4:2:0 to 4:1:1, and undergo more compression on recording since
it's 5:1.

Juan

Didi Schoeman
September 24th, 2003, 11:04 AM
Thank you everyone for the replies, I really appreciate it… seems having it transferred to Digi Beta or Beta SP would be the only open option to me when it comes to the broadcast masters which is ok.

I’ve somehow stumbled on DV Film’s Atlantis software:

http://www.dvfilm.com/atlantis/macversion.htm

Don’t know weather this software option will be able to deliver… does anyone have any experience with it?

I’ve downloaded a free trial version which I will be testing within the next two days or so… hopefully I’d get ok results… otherwise I’ll need to make another plan.

Will post details as soon as I’ve done the test.

Another system which might be promising is the CDM-830T Multi-system Converter which apparently provides broadcast quality conversion between numerous worldwide broadcast television standards. At least that’s what it says on their web site. Not cheap, but maybe an option if you use a Sony DSR-25 DVCAM deck to transfer your video to a standard DV tape.

http://www.converters.tv/converters/pal/ntsc.html?by=product_name&order=desc

Juan would that still have the same effect of bringing your quality down to 4:1:0 (If you use the DV format instead of mini DV???)?

Juan P. Pertierra
September 24th, 2003, 11:10 AM
No, there is no 4:2:0->4:1:1 problem since these converters seem to take analog inuts/outputs. I'm assuming that internally, it samples the signal and works in 4:2:2 or 4:2:1, so it does the conversion correctly. The only possible loss of quality I see is that you have to go analog and have the box resample the signal which is never desirable, but if you don't have anything else this could be your best option. It does say broadcast quality, you might want to check that they really mean it or ask for some demo footage?

Cheers,
juan

Jeff Donald
September 24th, 2003, 09:57 PM
Many of the professional level convertors work in 16 bit space. This helps keep the quality loss to a minimum.

Didi Schoeman
September 25th, 2003, 12:47 PM
As promised, the results of my Atlantis conversion software test.

I downloaded the Mac test version of the Atlantis PAL to NTSC conversion software from DV Film’s web site and used it to transfer a 5-minute PAL video, which was filmed on my PAL XL1s in normal mode and edited on Apple Mac’s Final Cut Pro 3.0.4

The Video clip had slow pans, fast pans, fast and slow camera movements, still shots, action shots with lots of body movement, dialog scenes with close ups on the characters lip movements.

The Atlantis software is very user friendly and I had no problem opening the video clip, which was saved as a self contained PAL FCP movie on my hard disc.

With a few selections from the settings menu I started the rendering process that converted the footage from PAL to NTSC, this took some time and needed about 3GB to process.

When the process was completed I simply renamed & saved the new NTSC version.

The results: Viewing the clip on the computer in Quick Time gave really good results, movement was smooth, dialog in sync, music and soundtrack was exactly the same as on the PAL version. In short I was very impressed… Comparing the original PAL clip and NTSC clip side by side in Quick Time players gave a remarkably similar picture.

Then I tried to import the clip into FCP by opening a new project and setting the project properties to NTSC. Importing the file was no problem, but unfortunately in the time line the clip had to be rendered and had a good one-inch black border around it. The result after the rendering process was not smooth at all, but I put all this down to me probably having a blond moment and missing a setting somewhere in FCP, which is needed to make the project a proper NTSC project… I didn’t have time to fool around with the settings...

I decided to import the clip to iMovie which had no problems with it, exported it via fire wire onto a mini DV using a Sony DCR-TRV27 NTSC camera… yes a small consumer digital handycam which I suppose does not deliver the highest quality, but nevertheless did the job.

Playing back the video on a 72inch television set and comparing it to the same PAL version on mini DV:

The picture looked good, movement was smooth, the colour was slightly less intensive and edges not quite as sharp as the PAL version, but then one has to remember that PAL does have a much higher resolution than NTSC which is probably the reason for this and the difference is barely noticeable.

I suppose one could also say that the PAL Video was slightly smoother than the NTSC version… again I am nit picking here, the results where really good and I am overall impressed with the software.

Atlantis does a good job with the transfer; it is ok for VHS copies etc. I would however not feel totally comfortable to do a transfer for a television program that needs to be broadcasted with it. For that I would rather send my PAL version off to a Video Duplication House and have a NTSC transfer done professionally.

I would still like to try out a professional 16-bit converter and look at the results that it delivers. The price tag of about $600 to $900 makes it a rather large gamble tough…

Hope the information is helpful to someone…

Regards

Jacques Mersereau
September 25th, 2003, 04:48 PM
<<<Now the million-dollar question, does anybody know of a fire wire system that would be able to convert a digital PAL signal into a digital NTSC signal without losing quality or sync?(edit) How do the video houses do it? >>>

They use a $50K+ Snell & Wilcox Alchemist Platinum Ph.C
Motion Compensated Standards Converter.
<from their site>
The Alchemist Platinum Ph.C motion compensated standards converter delivers the precision standards conversion performance only possible from using phase correlation motion estimation technology. Transparent conversion is achieved using a 3-stage 46 point temporal spatial filter. Internal processing is performed at 4:4:4 resolution and at a minimum of 12-bit precision.