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amv256
04-04-2006, 11:47 PM
NOTE: I'm not 100% sure this belongs here, but I'm an AE user so it seemed as good a place as any, but I'd appreciate a mod moving it if another forum would be more appropriate.

My background is in general 3D (using 3ds max) and mograf using After Effects. I've worked in broadcast, but everything thus far has been SD full-frame (720x480 4:3).

I'm now working privately on a short film that will be split between 3ds max and After Effects. However, I'd like to move into SD widescreen (16:9), as the full-frame look is just too "TV-ish" and doesn't have the cinematic quality I'm looking for.

Like I said, I've done a lot of work in broadcast and DVD, so the whole workflow is not new to me, I've just never TOUCHED widescreen. I've been Googling and trying to get a handle on everything I'll need to know, but there are a few things I still just can't seem to get clear answers on without asking directly:

1) First off, resolution: From what I've read, I almost got the impression that widescreen uses the same resolution of SD (720x480), but that the pixel aspect ratio is different and the image is stretched so that after the aspect ratio is applied, it fills a wider, shorter rectangle.

So just to verify what I've dug up in research, can someone give me a bottom line on SD Widescreen's resolution and pixel aspect ratio?

2) Next, with the new res and pixel aspect ratio, are there any changes to my workflow? I can't imagine any. Thus far I do my rendering and animation in 3ds max (of course), do compositing, mograf, certain effects, and general post processing in AE, and then either do a final edit pass in Premiere or just dump it directly to Encore for DVD burning. Viola, I've got a DVD or whatever ready for use.

Will working in widescreen entail any changes from what I've outlined above? I'd imagine the software would need to know I'm working in widescreen, since I'm sure the DVD is flagged differently in some way. Can anyone point me to references for the exact settings I'll need to ensure my tool path is aware of the switch to 16:9?

Basically, I'm an SD guy trying to nail down exactly what is necessary to do the same work in 16:9.

Thanks!

Integrity
04-05-2006, 02:13 AM
Yup. For DVD the resolution is 720x480 with a ratio of 1.2 (info direct from AE, look in the help files). There is a flag in the MPEG-2 stream to indicate what the ratio is intended to be, but the DVD player and its settings determine how it's shown. The image is stretched vertically (or squeezed horizontally, whichever way you look at it) in frame as you said, and on display is squeezed/stretched back. Anamorphic widescreen is a term for this.

amv256
04-06-2006, 02:44 AM
Okay, so I made a test DVD using the Widescreen 720x480 1:2 settings, ran it on the TV and everything worked.

The only problem is, it's not the widescreen I'm aiming for. It was letterboxed, but only about half as much as some of the test movies I compared it to, like Spider Man and the Matrix Revolutions.

I'm also noticing that in AE and Premiere I have an option for Anamorphic 2:1, which, according to the help file, is for dealing with film shot with an anamorphic lens. Now, this is all CG and mograf, so I don't have any real footage, but I'm looking for the same frame size as used in most widescreen feature films.

I've been digging more through helpfiles and Google, but I'm still trying to nail down the exact res/aspect for this particular mode.

Integrity
04-06-2006, 04:14 AM
The two most common (and really only ones that are really used nowadays) widescreen ratios are 1.85 and 2.35 (this is display ratio). Spiderman is 1.85 and The Matrix Revolutions is 2.35. Search and research these ratios to get a feel for which one you want to use, or you can make up your own but you need a custom ratio setting which I don't think Premiere or AE offers (well the versions I have anyway).

As for the test DVD, it was letterboxed most likely because your DVD player was outputting it as letterboxed. All of the recent DVD players should have an setting that you can set that forces how to display the video. Even my computer DVD application allows me to watch the DVD as its recorded stretched frame. All I do is simply uncheck the "Keep aspect ratio" setting. DVD player settings...well mine anyway...call it "4:3", and when I want the player to automatically stretch the frame back to 16:9 in a letterbox format (because I have a standard 4:3 TV) all I do is set it to "16:9 Letterbox" (which is the default anyway). I suggest playing around with your player's settings to see what comes out.

To finally answer your resolution question, all DVD's that I've ever seen always use the 720x480 resolution, which is the max. There's 704x480 (overscan deduction) and a couple others that are smaller, but obviously the manufacturers want to use all the quality DVD can offer. There's no 853x480 or other to match 16:9 if that's what your wondering (I got confused about this too when I was learning).

I'm a little confused on what you mean by "only half as much" widescreen, but all display ratios are confined, streched or squeezed inside this 720x480 resolution. For both 1.85 and 2.35 the actual file is squeezed/stretched inside a 16:9 flagged frame, with black bars on top and bottom, when doing it anamorphically. Some older DVD's didn't use the vertical resolution advantage of anamorphic and instead recorded a letterboxed image in a standard 4:3 frame. As for broadcast I have no idea how it works, but I'm going to assume that all standard analog broadcasts, when they want to display a 16:9 frame, HAVE to letterbox it. I think the digital broadcasts can be sent as 16:9 anamorphic, and the converter box acts like the DVD player, letting you chose how to display it. So if you're broadcasting you'll have to find out how it's being broadcast.

Taking your 2:1 as an example, this is what I would do. Since your going to DVD, and want to take advantage of the resolution gain in anamorphic 16:9, set your composition in AE to NTSC DV widescreen, import your 2:1 footage in AE, go to the file's individual Interpret Footage settings, and set it to 2:1 if it isn't already (you might have to resize). You can do the same for broadcast I would assume, but if analog I guess you'd have to letterbox it in a standard 4:3 frame.

Here are some links...

Doom9.net (http://www.doom9.net/) (go to The Basics on left, then Aspect Ratios explaind)
DVD FAQ (http://www.dvddemystified.com/dvdfaq.html#3.5)
Anamorphic - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Anamorphic)

I hope I didn't confuse (or offend if you already knew most of this) you, but I hope I helped.

amv256
04-06-2006, 06:05 AM
Great, it looks like it worked the way I thought it did. And don't worry, I really appreciate the help!

And what I meant by "halfway letterboxed" was a crude way of saying that it wasn't as skewed a ratio as movies like Spider Man and Matrix Revolutions. It was a wide screen, just not AS widescreen as I was looking for. :) Like you said, it's just a matter of working with a different aspect ratio.

So I understand how it's working, but I must say I'm surprised that even in the case of ultra-wide movies like Matrix and Star Wars, it's still using the same 720x480 frame and just stretched even further within the frame and displayed with a different aspect ratio. But that makes my job a lot easier, and since movies like that clearly aren't suffering in terms of image quality, I'm cool with it. :)

The only other thing I worry about a little is this-- are there any DVD players, presumably older ones, that can't handle aspect ratio settings other than 4:3 at all? I know image quality overall varies from player to player, but are any of the old/cheap ones going to literally display the widescreen image in a 4:3 frame, without the letterbox, and thus completely skewed vertically? I doubt they'd release AAA films with a risk like that, but then again, there must be SOME reason there's a market for full-frame DVDs. :)

Anyway, thanks again!

scrimski
04-06-2006, 07:10 AM
No specicifc idea for your problems/questions, but some tips: Always render out in square pixels from 3dsMax, do the 'pixel unsquarization' in After Effects. For testing purposes render out small clips about 30 seconds, with a lot of motion in the picture, burn them on rewritable DVDs(saves you blank discs), try them on as much DVD players as you can get your hand one, including an as-much-crappy-as-can one. If it works there, it usually works everywhere.

Mylenium
04-06-2006, 07:31 AM
The only other thing I worry about a little is this-- are there any DVD players, presumably older ones, that can't handle aspect ratio settings other than 4:3 at all? I know image quality overall varies from player to player, but are any of the old/cheap ones going to literally display the widescreen image in a 4:3 frame, without the letterbox, and thus completely skewed vertically? I doubt they'd release AAA films with a risk like that, but then again, there must be SOME reason there's a market for full-frame DVDs. :)

Anyway, thanks again!

There shouldn't be any problems. 16:9 was part of the standard ever since the DVD business started. So even the oldest player should be able to deliver a correct signal to the TV set/ monitor assuming your player is configured properly. TV sets that cannot display 16:9 natively will just add some more letterboxing to maintain the ratio.

Mylenium

amv256
04-06-2006, 07:38 AM
Thanks, I agree-- that's usually how I test things and I definitely planned on running these test discs through the gauntlet.

However, just when I thought I had all the kinks worked out, I'm clearly missing something again. I rendered a new test clip out of 3ds max at 720x480 with a 2.0 pixel aspect ratio. I imported that into After Effects, using the Anamorphic 2.0 setting, and everything was fine. I applied some text just to test things and then exported everything into Premiere to test the next part of the tool path. The problem is, neither Premiere nor Encore seem to have a setting for a 2.0 pixel aspect ratio (Widescreen is only acknowledged at 1.2), and as Integrity mentioned, none of these programs allow for a custom aspect.

So once my footage leaves After Effects, it appears that none of the other software understands anything other than 0.9 or 1.2. Strangely, Premiere allows me to interpret the footage as Anamorphic 2.0, but the sequence ITSELF can only be 0.9 or 1.2! What's the point of having a 2.0 clip if the sequence itself can't accomodate it?

So like I said above, 1.2 is not the ratio I'm looking for, and 0.9 is the standard full-frame. What option is left in order to produce wider footage in programs like Premiere and Encore? Without a custom option, there doesn't seem to be any way to physically work with such footage, but that can't be right.

Integrity
04-07-2006, 02:17 AM
There's only two ratios for DVD, 4:3 and 16:9; it's the same for broadcast. When you want to store a 2:1 ratio on DVD, you "letterbox" it inside 16:9, if you choose to do it anamorphically (that's what I meant by black bars on top and bottom for putting a 2.35 or 1.85 inside a 16:9 flagged frame); otherwise you could also do the old letterboxing in 4:3. This is why Premiere and Encore only let you chose between 0.9 and 1.2 for final output...because that's only what the standard defines.

For example, The Matrix Revolutions as 2.35...is put into a 16:9 frame with black bars on top and bottom. The DVD player plays it as a 16:9 frame, there is no 2.35 setting (but some TV's and players will allow you to crop it to 2.35 for better viewing purposes, but it is recorded in a 16:9 frame no matter what).

For your test clip, I suggest rendering out at 1.2 ratio, but before you render reposition your camera and set up some kind of temporary masking so you can see how your 2:1 ratio looks inside this 16:9 frame. But I would do as scrimski said, render in square pixels at the actual ratio (for example 2.35 a resolution could be 1142x486) at a higher resolution, then let AE do the ratio work. You would set a composition to DV widescreen, import your square pixel ratio render in AE, set it's Interpret Footage settings to square, then resize to fit it in the frame.

amv256
04-07-2006, 02:26 AM
Alright, that definitely explains it then. So to sum up, movies that appear to use a higher aspect ratio than straight 1.2 are encoded anamorphically in 1.2 and then further letterboxed into the desired shape. Makes sense, but it does suck to lose the vertical res. :)

And I really like the idea of working with square pixels, so I'll definitely just go with that approach and handle the anamorphic/letterboxing issues in a final pass so I don't have to take it into account at every step.

Looks like I've got it pretty much clear at this point. Thanks again!

amv256
04-07-2006, 08:20 AM
Whoohoo! It's all totally working. I've got a test DVD playing now that displays perfectly in 2.35. I did everything at 1128x480 using square pixels, so my entire workflow is very clean and simple. Then, as recommended, at the last stage I dump everything into a new 720x480 1.2 Widescreen composition and scale the width of the footage to 720, creating a slim letterbox. Once it's dumped to DVD, it plays in anamorphic 1.2 with the extra letterboxing squeezing it down to 2.35 and looks PERFECT. It's the EXACT same look as the example movies I mentioned, and is thusly exactly what I wanted.

So thanks again for all the help!

sjmcc
05-06-2006, 08:01 PM
Okay sorry to bring up an older thread but I have a question about this. I have my animation rendered out at 1124 x 480 and was curious about the final stage. How did you go about scaling the footage so that it would mantain the proper aspect ratio when it was rendered to the final movie and not be squashed or stretched. Sorry about the newb question but I just can't seem to get my head around this last part and help would be much appreciated.

Integrity
05-08-2006, 04:53 AM
Which frame format are you planning on using? ...Television or DVD? ... with 16:9 or 4:3?

sjmcc
05-08-2006, 10:56 PM
Thanks for replying. I rendered the frames 1124x480 at 30 per second. The ultimate goal is to get them to ntsc dvd with the matrix style anamorphic widescreen. I'm only testing a short animation at the moment to try to figure this out and work out the bugs for later projects. If there is a better resolution or frame rate to render at I could do this but I would really prefer to render out of my 3d program with square pixel to keep them easy to work with.

beenyweenies
05-10-2006, 06:27 AM
Thanks for replying. I rendered the frames 1124x480 at 30 per second. The ultimate goal is to get them to ntsc dvd with the matrix style anamorphic widescreen. I'm only testing a short animation at the moment to try to figure this out and work out the bugs for later projects. If there is a better resolution or frame rate to render at I could do this but I would really prefer to render out of my 3d program with square pixel to keep them easy to work with.

The matrix was shot CinemaScope, which has an aspect ration of 2.35:1. Since 720 is your width, divide that by 2.35 and you get 306 for the vertical size.

If you want to retain the full anamorphic, letterboxed look of the matrix on a standard-sized tv set, you should be able to render out of your 3d app at 720x306 and nest this into a 720x486 comp in After Effects. That's a hefty render savings over the 1124x480 size.

sjmcc
05-11-2006, 01:05 AM
Thank you that would definitley save on render times. The other thing I was wondering is if I render my frames as square pixels, do I need to scale the footage at some point, to achieve the proper pixel aspect ratio, so that my video won't be squashed or stretched on tv. If so, how do you properly determine the correct amount for Ntsc widescreen?

tb582
05-11-2006, 02:11 AM
What a great post...

I'm not sure I'm totally grasping the concept. I have a Sony VX2000 MiniDV Cam. Now it has a 16:9 setting. I have heard that it is not good because its not "true" 16:9 that it only stretches the video. Going by the other posts that is all that 16:9 is. They said that in order to not have the video looked stretched you need a camera that can support true 16:9 format... can someone clarify?

beenyweenies
05-11-2006, 11:13 PM
What a great post...

I'm not sure I'm totally grasping the concept. I have a Sony VX2000 MiniDV Cam. Now it has a 16:9 setting. I have heard that it is not good because its not "true" 16:9 that it only stretches the video. Going by the other posts that is all that 16:9 is. They said that in order to not have the video looked stretched you need a camera that can support true 16:9 format... can someone clarify?

Here's an example - most HD video is 1920x1080. If you do the math on that, 1920 has a 16 to 9 ratio to 1080 (hence the 16:9). True HD cameras can do this because the size of their CCD chips are 16:9 (for example, 9.6x5.4mm), which is why they call it "native" 16:9 - no squeezing or cropping needed, the sensors are already 16:9 and deliver images at this aspect ratio.

Standard DV cameras have 4:3 CCDs (for example, 7.2x5.4mm), so there must be stretching or cropping to get the 16:9 size out of these CCDs. You have two options:

1. There are anamorphic (widescreen) lens adapters for most prosumer cameras that will set you back about $800US. This is the better of your options since the squeeze is done optically, rather than electronically - which takes us to
2. Set your camera for 16:9 squeeze and your camera will electronically squeeze more image into a 4:3 size, and will "flag" the file as being anamorphic 16:9. The video is still shot 720x480 (standard definition), but when unsqueezed by your editing/gfx software fills a 16:9 screen. A word of warning here - quality is not so great using this mode with interlaced footage. If possible, set your camera to a progressive frame mode such as 24p. If not, expect quality problems.

Most apps know how to handle 16:9 flagged, squeezed footage without intervention on your part, but in AE you do need to set your composition as 720x480 DV WIDESCREEN, then nest the footage into this comp.

beenyweenies
05-11-2006, 11:28 PM
Thank you that would definitley save on render times. The other thing I was wondering is if I render my frames as square pixels, do I need to scale the footage at some point, to achieve the proper pixel aspect ratio, so that my video won't be squashed or stretched on tv. If so, how do you properly determine the correct amount for Ntsc widescreen?

You can scale it horizontally by exactly 10% (if you are using a 720x486 NTSC D1 comp) without any noticeable quality loss.

sjmcc
05-12-2006, 09:06 PM
Thank you. Your help has been greatly appreciated.

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