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Fred Helm January 6th, 2009 04:27 PM

Do I Understand This Correctly?
 
There are really only two aspect ratios on TV. Aspect ratio 4:3 which can be letterboxed to mimic 16:9 and then true 16:9 HD?

If I am shooting with any camera in SD and I choose to put my camera in a 16:9 apsect ratio, it is simply a prosumer tweaking of the image to scale out to a letterboxed 16:9? Not true 16:9 like if I shot in HD or HDV?

And finally, a standard definition DVD must be letterboxed (assuming your not in 4:3) unless you manipulate the image to fill the screen or somehow by blowing it up to hide the letterbox?

Blue Ray DVD is only true 16:9 versions available now?

A third apect presentation is showing up more and more on the networks, that being the inset 16:9 image that has a letterboxed border on all sides? What is this?

Perrone Ford January 6th, 2009 04:46 PM

Sounds like you've got it all right.

As to the last question, sounds like an error more than anything else.

Ervin Farkas January 6th, 2009 08:44 PM

Quote:

Originally Posted by Fred Helm (Post 990052)
And finally, a standard definition DVD must be letterboxed (assuming your not in 4:3) unless you manipulate the image to fill the screen or somehow by blowing it up to hide the letterbox?

NO!!! There are two types of standard def DVDs - 4x3 aka 'full screen', and 16x9 'wide screen'. In the old days, when all TV sets were 4x3, film studios letterboxed the wide screen source material to properly play it back on television screens.

In the meantime, on one hand DVD technology matured, on the other hand wide screen television sets came into our homes. So today, properly authored wide screen DVDs will play 'full screen' on 16x9 television sets; the same exact DVD, when played back on an old 4x3 set, will display the letterbox.

Chris Hurd January 6th, 2009 08:45 PM

Quote:

Originally Posted by Fred Helm (Post 990052)
A third apect presentation is showing up more and more on the networks, that being the inset 16:9 image that has a letterboxed border on all sides? What is this?

That's just a television that has not been properly set up.

Richard Alvarez January 6th, 2009 09:59 PM

[QUOTE=Fred Helm;990052]There are really only two aspect ratios on TV. Aspect ratio 4:3 which can be letterboxed to mimic 16:9 and then true 16:9 HD?

If I am shooting with any camera in SD and I choose to put my camera in a 16:9 apsect ratio, it is simply a prosumer tweaking of the image to scale out to a letterboxed 16:9? Not true 16:9 like if I shot in HD or HDV?



I think you misunderstand format resolution, and format itself. There are Regular SD cameras that shoot "True 16:9" - the XL2 has 'native' 16:9 format, as well as 4:3, and neither are HD. So its possible to shoot native SD in a 16:9 format, with no 'tweaking' of the image. The chips ARE 16:9.

When you shoot HD - the image is normally in the 16:9 format, yes.

Douglas Spotted Eagle January 7th, 2009 12:15 AM

[QUOTE=Richard Alvarez;990227]
Quote:

Originally Posted by Fred Helm (Post 990052)

When you shoot HD - the image is normally in the 16:9 format, yes.

If it's acquired and delivered in HD, it's *always* 16:9, unless it's been posted as something still in a wide format. There is no non-wide HD format for acquisition or HD delivery.
There surely is a lot of 4:3 content laid over wide with pillarboxing, it's a cheap way to repurpose standard def without stretching or rescaling anything.

Fred Helm January 7th, 2009 09:29 AM

ok, Im getting it better now. The reason for the post is trying to figure out DVDA's final renders. If I shot a wedding say on a Panasonic P2, Sony FX1 and so on- and it was all shot in SD 16:9, what are my options in DVDA for final aspect? Im trying to get an everyday, time after time, format in "full screen" but will accept letterboxed. With this footage Vegas will only show a letterboxed image or a 4:3 image. Rendering in Vegas as an Mpeg, then importing the file into DVDA for "burning" how do I get to a "full screen" without stretching etc...? Do I have to be using a camera with native 16:9 features in SD? Even if I shoot pure HD on the listed cameras, when vegas and or DVDA knocks it down, wont letterboxing appear for DVD playback on 16:9 TV's?

Ive never had a problem in DVDA because we always burn letterboxed. A client is asking why his SD "Dark Knight" movie is full screen and his wedding is not? Not a project killer, but a question I cant answer at this point.

John Miller January 7th, 2009 09:38 AM

Quote:

Originally Posted by Fred Helm (Post 990052)
If I am shooting with any camera in SD and I choose to put my camera in a 16:9 apsect ratio, it is simply a prosumer tweaking of the image to scale out to a letterboxed 16:9? Not true 16:9 like if I shot in HD or HDV?

That depends on the camcorder.

*Most* consumer level Sony DV cams, for example, do it the cheap way - slap a couple of black bars across the top and bottom or rescale the equivalent center portion to fill the image. But my first ever DV cam did it the real way - it had a 16:9 sensor and would record widescreen DV as exactly that. It took advantage of the electronic stabilization that required an oversized sensor. In widescreen mode, the extra space was used to get the wider extent of the field of view. My prosumer PDX-10 (may it r.i.p) did the same thing but my TRV50 does it on the cheap.

Of course, though I had a nice true 16:9 DV cam, none of the footage could be viewed on a TV correctly because SD widescreen CRT TVs weren't available here (unlike in Europe at the time). (I ended up writing something to turn my laptop into a real-time 16:9 -> 4:3 DV converter so I could hook it up between the cam and the TV).

Ervin Farkas January 7th, 2009 09:45 AM

Quote:

Originally Posted by Fred Helm (Post 990478)
Ive never had a problem in DVDA because we always burn letterboxed. A client is asking why his SD "Dark Knight" movie is full screen and his wedding is not? Not a project killer, but a question I cant answer at this point.

I would do it 16x9 "all the way" from shooting to editing project to final DVD. This way you will "future proof" your work, as 4x3 TVs will be history in a couple of years.

Do not "burn" letter boxed - let the DVD player "tell" the old CRT TV "this is 16x9", and it will automatically put up the letterbox. And on wide screen TVs it will fill the screen.

Ron Evans January 7th, 2009 10:43 AM

Most cameras do not use square pixels in their recording process. SD DV is 0.9091, anamorphic DV ( wide screen DV) is 1.212, HDV 1440x1080 is 1.333. For DV both are still 720x480 pixels they are just not the same aspect ratio for 4x3 and 16x9. A flag in the data file indicates if it is anamorphic or not. HDV is anamorphic by nature 1440 x 1.333 is 1920. IF one just assumes the files are square pixels one gets all sorts of squeezing of the picture etc. IT is important in editing to make sure that the clips on the timeline are at the correct pixel aspect ratio and that the output aspect ratio is also correct. Wide screen DV or output to MPEG2 for DVD widescreen should be held all the way through editing and authoring. The DVD player should be set up for the TV it is feeding and will then display correctly. I would normally use DVDlab for SD DVD and this has the capability to force the DVD player to play 16x9 which is how I set it up. This will display letterbox on a 4x3 and full screen on a 16x9 set. This is also true for playback from cameras, a16x9 playback on a 4x3 TV ( if set up correctly in the camera) will be letterboxed.
Seeing 16x9 letterboxed in a 4x3 box on a HD set coming from HD cable etc is a clear indication that the source is SD!!!!

Ron Evans

Terry Esslinger January 7th, 2009 12:33 PM

I don't know whats wrong with me, I must be getting senile. But the more I read about pixel aspect ratio and 4:3 vs 16:9 the more confused I get.
I know a 4:3 television (nearly square) and a HD television (rectangular, always - I think- 16:9). I know that Hollywod movies can be 4:3 (I think they are reformated to 'fit your TV screen' if you are a dinasaur and you lose part of the picture as the 'expert' does his pan and scan thing and decides what you should see. Or they can be "wide-screen" which is not necessarily 16:9 depending on whether it is cinimascope or panavision or etc. They can be different rations. Therefore you can still get black bars above and below your picture even on a wide screen tv that is set up correctly. HOWEVER watching commercial TV I will notice that occasionally I will get the rectangle within a rectangle (bars all the way around) as mentioned above... I have even made a DVD that showed up that way but for the life of me I cannot figure out how or why it happened. And I have not been able to do it again, though I have not really been trying.

Also there seems to be a difference between 'wide screen' and 16:9. You can end up with narrow black side bars that may or may not show up on the TV depending on overscan. This is apparently a result of pixel-aspect ratio differences. But the more I read the confuser I gets.

Ervin Farkas January 7th, 2009 12:47 PM

As far as film to video, there could be all sorts of horizontal black bars depending on how wide the filmmaker wanted his wide production to be. I've seen 'really wide' movies on video where the width was like four times the height, and they didn't do any pan-scan when they transferred to video. Go figure!

What you see nowadays on TV is an anomaly of the transition time; video engineers sometimes fail to properly adjust sizes/aspect ratios/whatnot and you end up with black bars all 'round.

To restore your self confidence, do one thing: shoot 16x9 - edit 16x9 - deliver 16x9. That's basically all you need to know at the moment... in a few years all the dust of this transition time will settle and we'll all watch 16x9 forever...

Or at least until the next video revolution...

Ron Evans January 7th, 2009 01:11 PM

I will maybe add a little more confusion for you. The camera creates the pixel ratio specified in the record setting and is almost never the same as the photo sensors on the chip. The cameras DSP takes in the information from the photo sensors and then interpolates the required output in the format specified. For instance my Sony FX1 HDV camera will create HDV at 1440x1080i( 1.333 pixel aspect ratio), 16x9 DV ( 1.212) or DV( 0.9010) all from the same sensor block. Pixel aspect ratio( whether the pixels are square or rectangular) is different from the shape of the display 4x3 or 16x9. Displays like LCD or plasma have square pixels so the rectangular pixels of DV wide screen and HDV have to be stretched over these square pixels. They further have to be scaled to the actual number of pixels on the displays( done in the display). If they are not scaled for the display the image appears squeezed( because rectangular pixels are now being viewed as square). Getting the pixel aspect wrong and the output from the NLE wrong with automatic scaling can result in some really strange squeezed letterbox output!!!!
With all this processing it is easy to see how noise and artifacts can be introduced and why some cameras are better than others. Same is true of displays or anything else in the chain for that matter.
Do what Ervin suggested. Shoot 16x9 and let the playback systems manage the output.

Ron Evans

Terry Esslinger January 7th, 2009 05:24 PM

Yep, a little more confusion!
Although I do understand "Shoot, edit, render 16:9 and let display and player do its thing.

Fred Helm January 7th, 2009 06:27 PM

im standing right next to you Terry!!!!


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