dwalby, as Musicvid10 responded in his post, it really should not be necessary to get into this very deeply. But I can see for some reason that you are extremely troubled over this by your "thorough" investigation.

What is truly different is the pixel aspect ratio (that's beside the screen size ratio) - so here's the gotcha. If you produce a DVD with incorrect information one way or the other there is going to be distortion. Occasionally you will even see this distortion in broadcasting when source is not transmitted and delivered correctly.

Take your source 4:3 NTSC and produce it 4:3 or take your source 16:9 Widescreen NTSC Widescreen and produce it with appropriate pixel and screen ratio to get no distortion on displays. Of course most LCD/LED screens today are expecting the widescreen source and production workflow.

videoITguy, I asked two simple questions, not sure how you were able to deduce that I am 'extremely troubled' by this, and thanks also for the condescending attitude regarding my 'thorough' investigation.

I tried two different settings, and to my eyes they both produced the same result, neither one was any more distorted than the other, so I thought I'd ask about it, but I'm sorry I brought it up.

The published specs of SD and Widescreen are everywhere including the help files of SCS products. The investigation with a tool like Photoshop would be clever except for very one important issue - you seemingly did not have the info at hand to know that the pixel aspect ratio was in fact different in the samples. This can be revealed in Photoshop like products - but only once you know what you are looking for.

Now you've touched on exactly what has me confused. I know how to read the rendering settings and understand the pixel aspect ratio is significantly different between the two formats. That's why I was expecting them to produce two different results.

I guess what I was expecting is NTSC 4:3 would produce a squarer result, which if played on my 16:9 TV would have black bands on all 4 sides to create the 4:3 aspect ratio. And NTSC widescreen would produce a 16:9 shaped result that would have black bands just on the top/bottom, but not the sides. What I'm getting is pretty much the same result using either format. And its the same whether I view it on the TV, or in the DVD preview window of DVDA. It looks like the widescreen format regardless of which option I choose.

I'm not trying to fix any problem, I'm OK with the result, I'm just trying to understand the process and settings in VMS. I usually have the project format set to the input video format of my source, which is 1280x720 MP4. In DVDA I can see the window shape change if I set the project format to widescreen or 4:3, but once I bring in the rendered files they both look the same in the preview window. Maybe they are being converted to match the output format selected in DVDA, regardless of the rendered format, so could that be why they look the same in the DVDA preview window? But when I select 4:3 format in DVDA, import a NTSC 4:3 format rendered file, and burn that to a DVD, I still end up with the widescreen look in the finished DVD on my TV. Maybe the TV is stretching it to 16:9 format as well?

Sorry to bother you with this pretty much academic question, but if you have any explanation I'd like to hear it.

what you are experiencing is both the result of your choice of workflow and the palyback by your DVD set-top player combination with TV - it all has a part in your results.. This topic is coverered endlessly in all the forums and I would suggest doing some deep research for an appreciation of the concepts.

I guess the bottom line is according to the rendering window "program stream NTSC" and "program stream NTSC widescreen" are both 720x480 formats. So the rendering operation is going to map 1280x720 source pixels into 720x480 rendered pixels in either case. So they probably should look the same even if they have different sounding names.

But its obvious you're annoyed by this topic, so I'll drop it for now.

The story behind PAR, DAR, and SAR is all on Wikipedia, and has been referenced here abundantly over time.

720x480 is NEITHER 4:3 NOR 16:9, but but that SOURCE is used to store either for correct display.

SARxPAR=DAR

It's exactly the kind of math we forgot promptly after fifth grade. . . .
;?)

For some reason everyone here automatically assumes I don't understand math, and can't read enough to understand PAR, DAR, SAR. I understand those concepts and can easily do the math.

The question I asked originally, and maybe I didn't ask it clearly enough, is if I use the same source for two renders, and render it with two totally different PAR values, as in NTSC (0.909) and NTSC widescreen (1.212) then why do they both look the same when I play the DVD on my widescreen TV. You keep saying if you have a widescreen source, use NTSC widescreen for rendering, and that makes sense to me, I'm not arguing that at all. But if NTSC 4:3 produces the same visual result, what's the point of having both options?

I'd like to get a little insight into what's happening during rendering, and during playback. I think the rendering operation simply maps pixels from one format (say 1280 wide) to the target (say 720 wide). In one sense, a pixel is just a RGB value in a file, its just a 24-bit value for that pixel location. What I don't know about, and was hoping someone could answer, is what effect PAR has on the pixel translation process. It seems to me that if you're translating 1280 pixels into a 720 pixel format, the translation would be the same regardless of PAR, but I suspect that assumption might be wrong. I'd also assume that those same 720 pixels would then be displayed at one width on a screen with a PAR of 0.909, and a different width on a screen with a PAR of 1.212. Seems to me that the pixels in the file could be the same in either case, and the display format would ultimately determine the width of the displayed image.

So based on those assumptions, I'm not surprised that both NTSC options produce the same visible result in my usage, but if I'm describing the process wrong please correct me where I'm wrong.

Edit: it just occurred to me that perhaps PAR is the same concept as dpi/ppi in a still image. The .jpg file format has a field available for a dpi/ppi value that's meaningless until you actually print or display the file somewhere. The pixel values are the same regardless of what size you print or display, so assigning an arbitrary ppi value is meaningless. Perhaps the same is true with the .mpg file format, it has a field for PAR, but until you display it somewhere, that value is meaningless also. It might indicate the original display intention, but the pixel values in the file are the same regardless of where they're displayed. The display device will determine how to use the pixel values to achieve the desired display result, but the pixels are not changed in the process.

As much as I love the math, I think it is a playback issue. Many DVD players have settings as part of their set up where the user asks try to play 4:3 material as widescreen.

Have you tried playing the DVDs rendered in the 2 ways on your PC making sure that any settings in the player are appropriate?

@Markk655

I suspect you're right about my DVD player playing back any 4:3 content as widescreen. The only other playback screen I've tried is DVDA, and both versions look the same there too. I can play both in 4:3 mode DVDA and they look the same, then play both in 16:9 mode DVDA and they still look the same (they're both wider than the 4:3 mode, but one looks just like the other). I think the root pixels are pretty much the same in both files, but would not claim they are literally identical.

see my edit above, it was posted a few minutes after your reply.

The set-top player tv combo has several settings on displaying content from 4;3 or 16:9 flags recorded on disc. In some cases the two pieces of equipment can override the flags.
Look for a set-top player internal menu and or setup screen - do the same for the TV.

Agreed on the TV/DVD player settings possibly coming into play, but let's talk about the DVDA playback being the same with either file.

I'm starting to think that the only difference between rendering to NTSC and NTSC widescreen is that a format field gets set that contains the rendering INTENTION. That intention can be, and is, overridden by any type of playback equipment to which you send the file. The playback equipment knows what format to display, and if that disagrees with what's in the format field in the file it simply ignores that field and goes about its business of displaying the image in the format its told.

If I set the DVDA project to 4:3 mode, and bring in the rendered file with the format field set to 16:9, DVDA says sorry but I'm not in 16:9 mode so I'm going to ignore that and play it in the format you have me set to, which is 4:3. Or vice-versa if you set DVDA mode to 16:9 and bring in the 4:3 file. It doesn't care which of the values it finds in the format field, it just displays in the format its told.

So I think this may be analogous to having a still image with the file info claiming the image size is 40"x60" at 30ppi. If you send that file to your printer and tell it to print at 4"x6", it ignores the fields in the file that claim its 40"x60" and prints it at the size you told it to print at, which is 4"x6". If you take the same image and make two copies of it, with one image size set to 40"x60" and another set to 4"x6", they will both print the same at 4x6, regardless of what the image size fields say.

I think this is what happens when you select either NTSC or NTSC widescreen, you're simply providing metadata that says you want to use this for a widescreen application, but the underlying pixels are the same as if you told the metadata you wanted it for a 4:3 application.

Dwalby, as you have discovered the pixel information is the same for 4:3 and 16:9 and the difference is that the file information contains different PAR information which tells your playing equipment how the pixels should be stretched (or squeezed).

But TV sets vary in how they handle this. With DVDs my seven year old Sony LCD TV automatically responds to the PAR information and adjusts the image correctly. You can see this happen as the disc is read. But my recently purchased Panasonic does not do this no matter how I fiddle with the settings. I have to manually alter the aspect ratio on the remote to get the correct picture. It puzzled me at first as I assumed all TVs behaved like my Sony. So I suspect your TV is behaving like my Panasonic.

Of course it's a whole new ball game if you are using a Blu-Ray player with HDMI connection.

i kind of given up convincing Dwalby of anything in this discourse...he seems to continue to just invent the scenarios he wants to believe and kind of neglects to put his ears to the ground which the rest of us keep asking the OP of this thread to do.

NTSC SD and NTSC Widescreen are two different things-they require different subsets of production workflows and if you don't pay close attention to your output you get rubbish.
In VegasPro it is horribly easy to create a NTSC Widescreen project - place NTSC SD 4:3 inside of that timeline and produce an output that is flagged 16:9 but plays the letterboxed sub set correctly. What is more if you produce the 16:9 DVD properly flagged it will play on the typical set-top player with TV correctly whether the TV is old CRT or new LED widescreen. Problems are solved.

Thanks Eric, since I have only one TV/DVD combo that I use for this, it appears as you say that my playback system defaults to showing anything and everything as widescreen format as I don't recall ever going into the menu system to request otherwise. I suspected that all along, but the fact that DVD Architect was doing the same thing is what took a little longer to sort out. After thinking out loud in a few posts I finally realized that DVDA was also ignoring the PAR values because it was simply matching both rendered videos to the selected project format. So I had two different systems both ignoring the PAR, but for slightly different reasons, and because the PAR was the only difference between the two renders, they both looked the same. Simple now that I've thought it through, but having never given it any thought before I wasn't sure if I was just missing some other detail somewhere that I wasn't aware of.

@VideoITguy

we must be on different wavelengths. for some reason you seem to think I've got a problem that I'm just not smart enough to figure out. You keep answering questions I don't ask, tell me techniques I already understand, and suggest I'm some kind of idiot who can't put 2 and 2 together to solve my problem. Let me repeat one last time, I don't have any problems with my project, its done, its good. I was just trying to understand how two different rendering options, for two different applications, produced the same visual result. Eric seems to have figured that out, and gave me a clear and concise answer without the condescending BS you've been shoveling throughout this entire thread.

Dwalby, if your TV "defaults" to 16:9 it's probably because you usually have it on that and when switching on it picks up the last setting.

As for DVDA I've not had any problems with compliant files from different people using different editing systems. DVDA has rendered them to DVD (without recompression) correctly. But should you have problems with DVDA not responding correctly to the PAR information you can correct it in the Track Media Properties.

Actually I share videoITguy's frustrations. You really have been looking for non existent moss under stones and making a simple issue complicated!

Anyway as an example of what can go wrong I once received a DVD which showed the videos square. They were 4:3 movies which had been placed in a 16:9 project. But they had been rendered to DVD as 4:3 (after all in the producers mind they were 4:3 movies!). So the result on the TV screen was a 4:3 image in which the original image was letterboxed with black sides reducing it to 3:3!!

OK, so I've been a pain in the butt, I was only trying to understand what was going on under the hood, and wasn't sure what or how to ask initially. Accidentally rendered 1280x720 to NTSC non-widescreen one time, and noticed it seemed to work the same as the NTSC widescreen in DVDA. Seemed strange at the time, so I thought I'd ask about it here. I guess this topic gets old to the regulars here so they're tired of discussing it over and over.

What you confirmed, that nobody else bothered to, (even though it was asked repeatedly), was that the two rendering formats are more or less the same pixels, just different PAR. I also didn't realize initially that DVDA was also ignoring the PAR, so once I figured that out then it all made sense. Can't learn if you don't ask.

DVDAPro does NOT INHERIT PAR if that is what you are getting at. NOTE It does NOT even inherit HD, it does not know if you are creating a DVD or a Blu-ray from a given media. These are the issues that are settled by creating a project of the specific type for the output that you want.

If I want a NTSC Widescreen 16:9 output to a DVD, then I must create that kind of project to begin with. Then import the appropriate media for the project spec.

Same applies to audio media set up.

I think a lot of casual users probably never think to look at project properties in DVDA. It's probably just assumed that DVDA does the correct thing given the media that's imported. I've caught myself a few times when i started making widescreen projects forgetting to change DVDA's properties from 4:3 to 16:9. And of course, DVDA will then create a disc flagged for 4:3 instead of widescreen.

Would be awfully nice if DVDA had a "match properties to source" the same way Vegas does, or at least a popup warning saying "do you really want to import 16:9 media into a 4:3 project?"

Of course, now, after lots of experience, whenever i launch DVDA the very first thing i do is open up the project properties window and make sure it's appropriately set for what i'm working on.

@videoITguy

"DVDAPro does NOT INHERIT PAR if that is what you are getting at."

If by inherit you mean set the DVDA output format to match the format of the input file, then no, I know it doesn't do that. I also know how to select the output format, so I wasn't asking about that. If by inherit you mean be aware of the input file PAR information at all, then yes, that was what I was asking all along.

DVDA PAR awareness was what I was trying to ask from the first post, but somehow it went off on a wild tangent. Mainly because I wasn't sure if it was a simple PAR issue, or something more, so I left the question a bit open ended, and I guess that created some confusion as to what I was asking about.

I accidentally rendered one clip to NTSC instead of NTSC widescreen and noticed no difference when I brought that clip into DVDA along with the other clips that were NTSC widescreen. So I did a comparison with two versions of the same clip, one rendered NTSC widescreen, one rendered NTSC, and saw that when I created a DVD in DVDA and previewed it in DVDA the two clips looked exactly the same. That was not what I expected.

I eventually realized during the course of this thread that the logical explanation was that DVDA was ignoring the PAR info and was just displaying the rendered images in whatever output format I had selected for the project. I think your statement above agrees with that claim. I was expecting DVDA to use the PAR info, not ignore it, so it took me a while to come around to that way of thinking.

In retrospect, if I had thought it through a bit more before posting here, I could have phrased my original question a bit clearer and saved people some time and frustration, my apologies for that.

I don't quite agree as my experience differs. If an incoming file is compliant, with the result DVDA doesn't have to recompress, then it will output to DVD with unchanged PAR. DVDA doesn't ignore it. It just doesn't fiddle with it. Consequently you can mix 4:3 and 16:9 on a DVD, and provided they don't need recompression, will play with their correct PAR. That's assuming, as we've discovered, your playing equipment responds to the PAR info and adjusts accordingly.

My experience is that the DVDA Project Settings only affect the menus, and files that need recompression because they are not compliant.

Yes, my TV/DVD player combo is displaying 4:3 as 16:9 anyway, so I pretty much discounted it right off the bat. So my only other evidence so far is the preview window of DVDA, which is where they both looked the same. However, I did notice that in the DVD menu window the icons were clearly different shapes, so the PAR info was clearly visible there. Its obvious DVDA is reading and retaining the PAR info. I created a DVD with both formats and burned it to a project file using DVDA. Then I played the DVD VOB files in VLC, and each clip retained its own format when I played it there. So I understand that the PAR info is being retained through the DVD burn process, and I finally figured out why the DVDA previews look the same. Its because my monitor can only display at its native PAR ratio, regardless of what PAR its told to drive. So it drives 4:3 and 16:9 the only way it can, based on its own physical dimensions, and they look pretty much the same.