XL2 PAL vs NTSC for potential film blow-up

[Alex Cano]

I don't think this has been discussed in depth now that the XL series has 24p...

I've been weighing down the option of buying a NTSC vs PAL XL2 camera. I will do a picture using the mini35, for which i would like to keep open the possibility of a film transfer down the road.

Now that NTSC has the 24p option, the choice doesn't seem to be as clear cut as it was before in terms of picture quality, because the PAL version would be at 25p and in a transfer to film I understand that the picture would be affected a bit by the conversion to 24 frames per sec. On the other hand, PAL just has more lines of resolution, 550,000 effective pixels in 16:9 compared to NTSC's 460,000 ... (then again everyone comments about the "sharpness" of the XL2 NTSC).

Are there any other factors to consider, PURELY in terms of the quality of the finished picture, trying to achieve a cinematic look, for or against either of these formats? Anything AGAINST the PAL 25p in terms of cinematic look, besides its increased resolution?

Besides quality of picture, what are the factors to consider re: purchase, real-world work flow, maintenance of a PAL XL2 in the US? I understand that in its day, it was easy to get a PAL XL1 in the US. Can an XL2 PAL be purchased in the US?

IF PAL IS THE ANSWER, what are the workflow issues that this raises in a NTSC country? What other PAL quipment would I need to get (I would edit on FC-HD with a G5), in order to have a finished film in the ol' hard drive?

Thank you very much!

Alex

[Jaime Valles]

I haven't used either one, but here's my comment nonetheless:

If you live in NTSC land, use NTSC. Yeah, PAL has more resolution. Whatever. Using PAL won't suddenly make your film look like Braveheart. The inconvenience of using PAL in a country that doesn't support it outweighs the increase in resolution, I think.

Spend your money on a good Sound Team, get a good DP, use lots of smooth camera moves, shoot in 24p, and nobody will care whether it was in PAL or NTSC.

[Dennis Hingsberg]

Alex,

Try this thread http://www.dvinfo.net/conf/showthrea...threadid=32069 for some extensive information on shooting PAL I wrote a while back.

I've used PAL for making films in an NTSC country, know many varying workflow methods and should be able to answer most of your PAL related questions.

Let me search the forum a bit more for other posts this has already been discussed in.

[Chris Mills]

Scott Billups has an excellent book on digital movie production and makes a number of solid arguments for using PAL versus NTSC.


It's well worth owning - or at least reading - for its many tips on how video works, aligning your camera, testing and testing and testing to make sure you get the best shots possible from your gear.

http://pixelmonger.com/home.html

In New Zealand, at least, nearly all televisions support both PAL and NTSC formats (as do most VCR and DVD players).

[Dennis Hingsberg]

Just remember now that 24P miniDV cameras are emerging, the number of arguments for using PAL versus NTSC have decreased slightly - as well as changed.

The main advantage of PAL "was" being able to get 24fps from it which not only yields film like motion characteristics, but the process for going to film is clean. ie. 1 frame of PAL goes to 1 frame of film. The process for converting 60i NTSC to 24P for film transfer has been around for a long time and YES its been refined and processes have dramatically improved - but it involves blending and contorting fields and frames and in the end what you end up being left with is not as good as 1 frame of video going to 1 frame of film. Now that 24P miniDV is available - NTSC can also go to film using a 1 to 1 frame transfer method.

24P NTSC for film transfer - best option, cleanest.
60i NTSC for film transfer - okay, but not the best.
30p NTSC for film transfer - not okay, bad results - avoid.

The second advantage of PAL (which is still an advantage today) is the 20% larger frame size. Remember, once you add cine bars in post to any miniDV footage you are going to lose 20% doing so. Shooting PAL gives you back what you lost. A quote from my other post regarding cropping the top and bottom of video:

..if you shoot NTSC and transfer to film your resolution is less than NTSC. If you shoot on PAL, your resolution after 35mm transfer equates to NTSC!

However that was more true before the XL2 because up until then we were only using 4:3 CCD's to capture our images and cropping them to look 16:9. Now that you can shoot 16:9 with the XL2 going to film with a PAL or NTSC version is going to have more resolution then we've ever seen transferred to film - but of course the PAL version will always have 20% more.

Confused yet?

The final reason for shooting on PAL and probably the least of anyone's concern is that color is stored and therefore reproduced more accurately then with NTSC. Since your footage will likely go through an intense post production stage, it really won't impact you at the end of the day.

Shooting on PAL living in an NTSC was fun for me (painful for those around me) and making my films I learned a lot about the conversion process to NTSC & 24P, various workflows... but now that the XL2 is out and can shoot 16:9 without losing 20% in post due to adding fake bars - I've feel I've gained back what I would have lost if I stayed with NTSC on a 4:3 CCD system.

What I suggest now to anyone considering PAL is to only shoot PAL if you know you are going to film, and if so use the XL2 because you are going to get 16:9 + 20% resolution.

[Alex Cano]

Dennis, great post above! You put all the different points and arguments that I've heard in my research (and some new ones: so that's why they have that joke, NTSC=Never The Same Color...) in a very concise way, and with great perspective.

Let me see if I have it straight (and add some comments of my own!):

PICTURE QUALITY:

NTSC advantage: you get 24p, frame-to-frame transfer to film.
PAL: You get 20% increased resolution, accurate colors.

NTSC disadvantage: lower resolution.
PAL disadvantage: the transfer from PAL to NTSC for presentation purposes is involved, degrades the image somewhat, the sound is a bit distorted, noticeable to varying degrees but specially with music. The transfer from 25p to film is close but not exactly frame to frame (some motion/sound artifacts resulting from this?)-- or do I have this wrong because you would edit the 25p footage into a 24p timeline (resulting in the issues above), and output that 24p timeline for the film transfer, frame to frame.

WORK-FLOW ISSUES:

NTSC advantage: Camera available and serviceable in the US, compatible with all accesories, you can edit in a 24p timeline, and output that directly for a film transfer.
PAL advantage: I can't think of any (all its advantages are picture quality related).

NTSC disadvantage: None, except you would have to convert to PAL for festivals in Europe.
PAL disadvantage: Getting the camera, possible import taxes, having it serviced, getting a PAL deck, renting at least a NTSC/PAL monitor, the work involved in transfering PAL to NTSC.

Okay, well the good news is that I have (at least I think I have) a good understanding now of all the pros/cons.

The bad news is that I'm still undecided :-)

Alex

[David Lach]

If you're ONLY planing to transfer/upres either to film or HD for screening, I think PAL is still the best option regardless. I've been toying with this for months before settling, but in the end, I decided to go with the NTSC version and accept the 20% resolution decrease, because I plan to make some money too with that camera by shooting stuff that will likely end up on NTSC TVs.

While shooting a feature at 25p and then transfering to film at 24p is a breeze and will most of the time be done at no extra cost by transfer houses, having to convert everything you shoot in PAL 25p or 50i to NTSC is a pain, especially when doing this professionally, where time is money.

Also, I've encountered a few artifact problems when converting some PAL footage to NTSC, because it not only has to change the frame rate, but it also needs to convert from 576 lines of vertical resolution to 480.

And on top of that, the process takes time. It's no big deal for features and shorts, even documentaries, because obviously, you won't be rendering 3 projects a week, but if you live in an NTSC country and plan to make a living out of this camera too, forget it, it's not worth the hastle.

[Alex Cano]

^That's a good point too, because even though I'm getting the camera for this project, I also want to use it further to make some money in my market, projects that would go to NTSC TV only.

As far as extra time spent... I don't suspect I'll be so busy (hopefully I'm wrong, and by that point there'll be affordable/usable 24p HD and I'll use the cash pouring in to buy it [laughs maniacally]), but not having done it I'm worried about the difficulty of the NTSC-PAL transfer and the possible lowering of the image quality.

Okay, I'm tossing a coin. Heads=PAL, Tails=NTSC.

It was tails. (Goes off to buy NTSC model...)

Alex

[Alex Cano]

(Stops, calls transfer houses again with info gained on thread)

The folks at Swiss Effects will swear by PAL. I just spoke with another good transfer house, DV Film, they said that they still recommed shooting PAL, even with NTSC's 24p.

That 20% increase in resolution sure is welcome at the time of blow up to film (or for Digital Projection also)!

They said that I would edit footage on a 25p timeline (that all NLEs have this ability) and give them that output for blow-up.
Things that would have to be purchased: a PAL monitor for editing, a deck, lots of beer.

(Goes off to buy beer)

Alex

[Dennis Hingsberg]

<<<-- Originally posted by Alex Cano :
PICTURE QUALITY:
NTSC advantage: you get 24p, frame-to-frame transfer to film.
PAL: You get 20% increased resolution, accurate colors.
>>>>

PAL to film transfer also gets 1 to 1 frame transfer, but at the expense of stretching the sound track by 4%. For dialog a 4% change is not noticable, but for music it is so it is better to only add music after you have done your 4% video stretch, for example during post edit your PAL footage on a 24fps timeline.

<<<-- Originally posted by Alex Cano :
NTSC disadvantage: lower resolution.
PAL disadvantage: the transfer from PAL to NTSC for presentation purposes is involved, degrades the image somewhat, the sound is a bit distorted, noticeable to varying degrees but specially with music. The transfer from 25p to film is close but not exactly frame to frame (some motion/sound artifacts resulting from this?)-- or do I have this wrong because you would edit the 25p footage into a 24p timeline (resulting in the issues above), and output that 24p timeline for the film transfer, frame to frame.
>>>>

NO - the transfer of PAL to NTSC will not degrade the image depending on how you attempt your conversion. If you conform your PAL footage to a 24fps timeline and edit that way, you can use After Effects to perform a 3:2 pulldown on the footage which is exactly the same process used to convert 24fps film to NTSC. So now EACH PAL frame gets it's own NTSC frame and then is repeated using the 3:2 pattern to fit. (You even end up with that "film look judder" that you see with quick panning objects or anything that moves horizontally.) Again, all you have to do though is adjust your dialog sound track by 4%. A simple program like Adobe Audition will do a great job stretching and keeping the pitch of your sounds.

As for the "artifacts" everyone is talking about:

This is really complicated but the artifacts most people talk about when you resize a PAL frame of 720x576 to NTSC 720x480 frame truly depends on how exactly the frame rates were converted from PAL 50i to NTSC 60i. It also depends on which is converted first, the frame size or the frame rate. Atlantis is the worst I've seen to convert both frame rate and frame size due to lack of manual control over the process of conversion.

In more technical detail, resizing an image frame can be done using a variety of resizing and resampling methods. For example, bilinear, bicubic, lanczos, etc.. and changing frame rates from PAL to NTSC usually involves a really good deinterlacing algorithm and pull down method all at the same time - no off the shelf program is going to do both very well. The method I described above is your BEST option plus it yields true "film look" motion characteristics.

<<<-- Originally posted by Alex Cano :
WORK-FLOW ISSUES:

NTSC advantage: Camera available and serviceable in the US, compatible with all accesories, you can edit in a 24p timeline, and output that directly for a film transfer.
PAL advantage: I can't think of any (all its advantages are picture quality related).

NTSC disadvantage: None, except you would have to convert to PAL for festivals in Europe.
PAL disadvantage: Getting the camera, possible import taxes, having it serviced, getting a PAL deck, renting at least a NTSC/PAL monitor, the work involved in transfering PAL to NTSC.
>>>>

PAL - you can also edit on a 24fps timeline, just stretch your audio using a good program and then bring it back in on your timeline - and then add your music. The added processing time to convert footage is minimal this way. Also what ever you do, don't edit 25fps and try all this stretching business later!

[David Lach]

I've tried Atlantis and indeed didn't think it was doing a very good job. But this thing is slow as hell, hence the workflow issue. Again, not a big deal when finishing a feature or documentary, but for wedding/event videographers, for example, that want to shoot their personal stuff for screening but also need to use the cam in a professional manner to shoot, edit and render multiple projects a week, those PAL - NTSC systematic conversions can become quite a burden.

[David Lach]

Also, just a reminder about splitting hairs, that 20% resolution increase won't make or break your movie. It won't look like Lawrence of Arabia because you're using PAL, and it won't look like Uncle Joe's travel footage because you shot it NTSC either.

We're not talking quadruple, triple, double, not even half more resolution here, so although it will be noticeable, it won't make the difference by itself (whatever that difference might be to you). If your movie is good and captivating and was shot in NTSC format, you'd be hard press to find one spectator that would come out of the theater saying, "yeah, it was all right, but I wish it had 20% more resolution". Most (if not all) of them would never be able to tell. Just tech freaks like us would.

I always need to remind that to myself because often I forget to look at the big picture (literally in this case) and stop being so picky about the details. If your only concern is screenings, sure, go ahead and buy the PAL, you won't regret it, but I myself decided to make my life that much easier by going NTSC (for a lot of reasons, time, money and infra-structures) and decided that 20% resolution increase wasn't worth the hastle (it's 20% for crying out loud). Lighting and framing is and will always be more important.

So get whichever you feel more comfortable with and stop talking, start shooting! ;-)

[Alex Cano]

^^^

David,

Part of the issue for me is that I'll be using the mini35, which decreases resolution even further. I think it was Barry Green who calculated it at about (there's that number again) 20% decrease using the mini35.

So, you start out mith miniDV, which is not the best format for a feature because of nothing else but the lack of resolution when compared to larger formats, get NTSC which has 20% less resolution than PAL (and that's not splitting hairs for me, 20% is a fifth increase. I haven't seen a back to back comparison with same set-up/lighting/etc of PAL vs NTSC, but I would suspect that's a noticiable gain), and THEN decrease it further with the mini35 (and from the ZGC DVD I saw, there is a certain softness there)... it doesn't leave you with much.

If I were to buy PAL, anybody know a good dealer. Has anyone used EXPANDORE (www.expandore.biz)? Anyone know how much taxes you have to pay customs?

Oh, and I know that it won't make or brake the film, but trust me, I'm as anal about EVERYTHING (in fact, too much so, I investigate everything to exhaustion I think) as I am with this, and I don't shoot until February regardless. Just wanna get the right tool and start practicing.

Thanks guys!

[Dennis Hingsberg]

Alex - I'd love to read that thread by Barry Green if you could find it since I only shoot with the mini35. To my knowledge there is no decrease in resolution when using the mini35 so I'm somewhat curious to see what Barry's written.

Using 35mm lenses will resolve more lines of resolution than your standard stock camera lens, so if there is any decrease in rez using the mini35 it would have to come from the prisms and ground glass - interesting.

[Alex Cano]

Dennis, I can't give a link, what I did was do a search for "mini35" in both this and the dvxuser forums, and then copied and pasted all the comments I found interesting into a word document, for me to read back to back. Here's what Barry had to say, and it comes form the dvxuser forum (dated 10/15/04):

"Because you're photographing an image that's being projected onto a piece of ground glass. It's quite a bit softer. I don't know exactly how much but I'd guess on the order of 20% or so."

and on another dvx thread(dated 10/2/04):

"Regarding film blow-up: I've done this, and the mini35 footage is definitely softer than non-mini35 (...) It wasn't overwhelmingly softer, but soft enough that I would think twice before committing an entire project to that process"

This is in regards to the mini35/dvx combo. The XL2 configurations should be sharper, even in NTSC.

Alex