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Old February 4th, 2004, 02:25 PM   #1
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Magic Bullet's PAL to NTSC conversion

I spent some time poking around the message board, but didn't really find anything dealing directly with Magic Bullet's ability to take PAL footage and convert to NTSC.

Does anyone have any experience with this? If so, how were the results?

Thanks to all who answer!
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Old February 6th, 2004, 06:17 AM   #2
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I dont have any direct experience, as i only own NTSC cameras.

Post some PAL footage and i'd be happy to try to convert it to 29.97p in MB and see how it comes out.
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Old February 6th, 2004, 09:17 AM   #3
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PAL to NTSC

Thanks for the offer, but I don't have a PAL camera yet. I will be getting one soon. From what I've read, and from a couple of people I have talked to, I hear that the results are very good - i.e. footage shot from a PAL XL 1S looks better in NTSC then footage shot on a NTSC XL 1S, because of the extra resolution, and because PAL is 4:2:0 vs. NTSC 4:1:1

Has anyone heard differently?
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Old February 12th, 2004, 10:51 PM   #4
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You might want to read some threads I posted in the P+S Technik forum here on this site. I live here in Toronto, Canada and shoot with a PAL version of the XL1S to make films.

I have written about NTSC vs PAL on my website, but to summarize:

PAL resolution is 720 x 576, NTSC is 720 x 480. This means PAL has a higher vertical resolution and considering miniDV has poor detail with wide shots, every bit extra resolution counts.

Because the frame rate of PAL is slower than NTSC is means there is extra "digital data" that can be go on the tape so with PAL they use a better/higher color sampling process.

If you like the motion characteristics of the 24fps film rate, then you will like PAL because it is 25fps which very closely matches the frame rate film is shot at.

For those who think the DVX100 is cool, PAL is actually just as cool if not more cool because it is difficult if not impossible to see a difference between 24fps and 25fps - plus PAL will give you higher resolution than any NTSC digital camera out there.

If you use your computer for editing, you can edit PAL the same way you edit NTSC video - your computer does not care. If fact you can edit your whole project as PAL and distribute it as an AVI or MOV file and any PC will play it. Computers do not care about format! You only need to convert your PAL footage to NTSC if you want to play it on a NTSC television from DVD or VHS - and then you do need software like Atlantis which does a really good job without stretching your audio and changing its speed.

Lastly, don't be sold on shooting progressive video - this can easily be done with software and in most cases without sacrificing and vertical resolution. And actually when I shoot with PAL and then convert it to NTSC I get the same effect as video that was shot progressively even though I didn't shoot progressively!

I hope I've helped answer your question?! Let me know if you have any more.
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Old February 13th, 2004, 12:03 AM   #5
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Thanks!

That definitely covered all of my concerns, and, through the generosity of a fellow DVinfo group member, I will soon be the proud owner of a PAL XL 1S!

Thanks for your help guys; you have proved once again that this forum is definitely an invaluable resource to the DV community.
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Old February 13th, 2004, 07:29 AM   #6
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I should have also mentioned that if you want to transfer your DV footage to a 35mm film print afterwards (required for some film festivals and also carries more respect from potential distributors) PAL will yield slightly better results over the NTSC signal.

Don't get me wrong, we live in a major technilogical era and many digital to film transfer houses have MASTERED converting NTSC at 60 interlaced/30frames per second to 24 film frames per second but all things considered, PAL will give you slightly better results because of the higher resolution and frame rate.

Below are some other posts here regarding PAL/DVX100/Progressive, etc...

http://www.dvinfo.net/conf/showthread.php?s=&threadid=16012

http://www.dvinfo.net/conf/showthread.php?s=&postid=111581#post111581
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Old February 13th, 2004, 01:34 PM   #7
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<<<-- Originally posted by Dennis Hingsberg :

PAL resolution is 720 x 576, NTSC is 720 x 480. This means PAL has a higher vertical resolution and considering miniDV has poor detail with wide shots, every bit extra resolution counts.

-->>>

This is true. However, in reference to the question about "does PAL-originated material, converted to NTSC, look better than NTSC-originated material" the answer is a resounding NO. PAL has higher resolution, but you throw that resolution away when converting to NTSC. Furthermore, because of the difference in frame rates, PAL to NTSC conversion can introduce significant motion artifacts. Finally, PAL's color sampling, at 4:2:0, has to be converted to NTSC's, at 4:1:1, which means much less color resolution (an effective 4:1:0).

<<<--
Because the frame rate of PAL is slower than NTSC is means there is extra "digital data" that can be go on the tape so with PAL they use a better/higher color sampling process.
-->>>

Untrue. PAL's higher resolution eats up that digital data space. Both NTSC and PAL net out at exactly 25 mbps. PAL has fewer, but higher-resolution frames; NTSC has more, lower-res frames, but the pixel count per second comes out the same. PAL's color sampling process is different, but not higher. Adam Wilt wrote an article about PAL's color sampling, showing that it has different artifacts than 4:1:1. Not necessarily "better", but different.

<<<--
If you like the motion characteristics of the 24fps film rate, then you will like PAL because it is 25fps which very closely matches the frame rate film is shot at.
-->>>

Don't mean to be disagreeable, but this just isn't accurate. PAL isn't 25fps. PAL is 50i. PAL looks very much like conventional 60i video. Now, if you're shooting in frame mode, then yes, you're getting 25 distinct frames per second, which almost perfectly matches the motion characteristics of 24fps film. But PAL by itself, without using frame mode, is 50 interlaced fields per second, which looks nothing like film, it looks very very much like "video".

<<<--
For those who think the DVX100 is cool, PAL is actually just as cool if not more cool because it is difficult if not impossible to see a difference between 24fps and 25fps - plus PAL will give you higher resolution than any NTSC digital camera out there.
-->>>

Well, again this statement would need some clarification. An NTSC DVX100, shooting progressive/thin line mode, is much higher resolution than any PAL camera (except a PAL DVX100, of course). All interlaced cameras use line-pair summation to blend fields together to reduce interline flicker. The result is a 25% loss in resolution from the pixel count -- so no interlaced PAL camera is going to deliver more than about 430 lines. Progressive-scan cameras (like the DVX and SDX) can bypass that blending filter, to deliver the full raw resolution. An NTSC DVX in thin line mode will deliver a true 480 lines. And a PAL DVX will do a true 576.

Furthermore, if you're using frame mode to get a film look, you'll lose another 10-15% of resolution, putting PAL frame mode at around 380 lines. That's still higher than any interlaced NTSC camera (those max out at about 360 lines) but not in comparison to an NTSC DVX, at 480.

And once you go to NTSC? The DVX will be far ahead, because it won't have undergone a 25p->24P conversion (or 50i->60i, or 50i->24P, or any other conversion) and it won't have suffered the color space decimation (4:2:0 to 4:1:1, yielding 4:1:0).

<<<--If you use your computer for editing, you can edit PAL the same way you edit NTSC video
-->>>

This is totally accurate, most modern editing systems are multistandard-capable. Even the newer decks are multistandard -- I have a JVC BR-DV3000 which has a switch on it, you can select PAL or NTSC on it. But you'll also need a PAL monitor if you want to be able to see what you're editing. This is obvious, of course, but just pointing it out -- that's one more expense if you decide to go the PAL route.

<<<--Lastly, don't be sold on shooting progressive video - this can easily be done with software and in most cases without sacrificing and vertical resolution.
-->>>

That's simply not possible. You will absolutely lose resolution. It may do a pretty good job and the resolution loss won't be too noticeable, but you definitely will be losing resolution.

Someone did a thread here not too long ago where they compared all sorts of de-interlacing options, including Magic Bullet. Every one of them showed significant resolution loss. It's mandatory.

Actually, the way to lose the least resolution is to use the frame mode -- that only costs about 10-15%. I haven't seen a post-processing conversion system that can do as well as the in-camera hardware. But true progressive is dramatically higher than frame mode.
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Old February 14th, 2004, 10:48 PM   #8
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<<<-- Originally posted by Barry Green :

However, in reference to the question about "does PAL-originated material, converted to NTSC, look better than NTSC-originated material" the answer is a resounding NO. PAL has higher resolution, but you throw that resolution away when converting to NTSC.

-->>

If the conversion from PAL to NTSC is performed digitally then I might agree that the extra resolution is thrown away. But consider converting DV PAL to NTSC uncompressed (Y/C) and the resolution and image detail will in fact better than NTSC footage shot with the same model camera (XL1 in this example).

You're claim is based solely on pixel count and pixel conversion, but my claim is based solely on lines of resolution. Remember that PAL produces 625 lines of resolution while NTSC offers only 525. If you copy from a source offering more lines of resolution it will surely produce higher quality. It's like the difference between copying from VHS to VHS versus DVD to VHS.

<<<--
Furthermore, because of the difference in frame rates, PAL to NTSC conversion can introduce significant motion artifacts.
>>>--

I've yet to see any motion artifacts when converting PAL to NTSC and I do it a lot. But given the number of different methods to convert PAL I'm sure there have been cases. If anyone shooting PAL is experiencing motion artifacts I'd be curious to know what process you are using, perhaps we can exchange methods.

<<<--
Finally, PAL's color sampling, at 4:2:0, has to be converted to NTSC's, at 4:1:1, which means much less color resolution (an effective 4:1:0).
>>>--

I would not agree that the color resolution of PAL is "less"
than NTSC in general or upon conversion. I'd like more of a technical explanation on how you derive to this. However what I did find on Adam Wilt's site were comments that characteristics of 4:2:0 showed more evenly-balanced subsampling than 4:1:1 when looking closely at the image detail where color changes are present.

<<<--
Both NTSC and PAL net out at exactly 25 mbps. PAL has fewer, but higher-resolution frames; NTSC has more, lower-res frames, but the pixel count per second comes out the same.
>>>--

Though the data bandwidth may be the same, PAL uses 12 tracks at 10 microns per track to store one frame of video while NTSC uses 10 tracks at 10 microns per track. This means that PAL gets an extra 20% of track per frame to store its video and audio. My understanding was that this attribute is what allowed the PAL format to have its own dedicated color space as opposed to NTSC which does not.

<<<---
Don't mean to be disagreeable, but this just isn't accurate. PAL isn't 25fps. PAL is 50i. PAL looks very much like conventional 60i video. Now, if you're shooting in frame mode, then yes, you're getting 25 distinct frames per second, which almost perfectly matches the motion characteristics of 24fps film. But PAL by itself, without using frame mode, is 50 interlaced fields per second, which looks nothing like film, it looks very very much like "video".
>>>---

Yes this is true, the PAL footage must undergo proper deinterlacing for a progressive look or be shot in the frame mode but I would opt for deinterlacing in post over frame mode on your original footage.


<<<--
Furthermore, if you're using frame mode to get a film look, you'll lose another 10-15% of resolution, putting PAL frame mode at around 380 lines. That's still higher than any interlaced NTSC camera (those max out at about 360 lines) but not in comparison to an NTSC DVX, at 480.
>>>--

Actually frame mode loses about 25% of resolution which is why I suggested doing it in post instead of in the camera itself. Good deinterlacing software will only deinterlace the areas with motion in the frame, not the whole frame so for the "most" part the whole frame's resolution is preserved. Of course if the whole frame is moving... well that's gotta be a different story.
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Old February 15th, 2004, 08:31 AM   #9
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<<<--
Finally, PAL's color sampling, at 4:2:0, has to be converted to NTSC's, at 4:1:1, which means much less color resolution (an effective 4:1:0).
>>>--

"I would not agree that the color resolution of PAL is "less"
than NTSC in general or upon conversion. I'd like more of a technical explanation on how you derive to this. However what I did find on Adam Wilt's site were comments that characteristics of 4:2:0 showed more evenly-balanced subsampling than 4:1:1 when looking closely at the image detail where color changes are present."

All depends on how you convert it! If you were to do a "straight" conversion, then the final colour sampling could be very low indeed. However, if you upsample the 4:2:0 to 4:4:4 before converting back to 4:1:1 the loss should be minimal.

Also, I don't think that shooting PAL for an NTSC end product is a good idea. There's no way to do a perfect conversion from PAL to NTSC, and you're just going to loose any of PAL's advantages in the process because PAL starts only just a little higher than NTSC in quality, and the conversion process is going to reduce that quality.

"My understanding was that this attribute is what allowed the PAL format to have its own dedicated color space as opposed to NTSC which does not."

PAL is 4:2:0 which effectively records a quarter resolution colour signal. NTSC is 4:1:1 which effectively records a quarter resolution colour signal, but in a different pattern. They're both as bad as each other in information terms.
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