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Discussion Starter · #1 ·
I wanted to start a new thread on this topic since I haven't found a great answer in one single place for it. Most google and avsforum results were only covering situations (answer-wise at least) where people didn't know to set their dvd player to 16:9 or didn't know about 2.35:1 DVDs versus 1.85:1 and such. So this is to explain what HDTV aspect mode to use for DVD hookup and why. I believe I have this right but super-techies (after reading the whole thing please) can correct me if not.


When I first hooked up my DVD player (cheapo Magnavox MSD 126) to my new HDTV (Vizio SV420M - 1080p) via the component cables, it was placing the picture in a 4:3 format with vertical letterboxing (black bars) on the left and right for a 1.85:1 ANAMORPHIC widescreen DVD and for a 2.35:1 anamorphic DVD it had a letterboxed image (top and bottom grey bars) framed INSIDE a 4:3 letterboxing, effectively putting black bars around the whole picture and only using a small chunk of my widescreen TV.


I went into the DVD settings and saw it was set on 4:3 letterbox output. I switched it to 16:9 and thought problem solved. Well the image was still being displayed in the same aspect ratio it seemed.


My TV has 4 wide mode settings in this component input: Normal, Panoramic, Zoom 1 and Zoom 2. It identifies the input source of the DVD player as 480p SD (once I enabled progressive scanning on the DVD player).

I'll discuss these 4 wide mode options using the 2.35:1 anamorphic DVD mentioned above. [For those who don't know, HDTVs are in about a 1.78:1 ratio (16/9). So a 1.85:1 filmed widescreen movie will basically fit your TV, whereas other widescreen movies can be in an even wider aspect (thinner vertically). 2.35:1 is very common nowadays. So ANY widescreen movie that is higher ratio than 1.85:1 will still have at least some black bars on top and bottom, regardless if it's BlueRay, DVD, through HD cable source, etc. Don't be concerned about top and bottom black bars only on those movies.


OK so for a 2.35:1 anamorphic movie with DVD player set to 16:9 with the HDTV wide mode setting on...

Normal - this is where it does the box inside a box issue (bars on all sides) - the actual movie image is 27.25" x 16.75" which is a 1.62:1 aspect ratio. I explain why DVD can start off horizontally "shrunk" like this below.

Panoramic AND Zoom 1 - the image is pulled wide across the whole screen width and with the same height as Normal setting - 36.5" x 16.75" (2.18:1 aspect ration) - so you can see that this is at least close to the true aspect ratio of 2.35:1.

Zoom 2 - the image covers the entire screen - 36.5" x 20.5" (1.78:1 aspect ratio) and cuts a tiny bit off the top and bottom of the image.


Until I did the math, I had thought Panoramic and Zoom 1 were "stretching" the image wider than meant but as you can see those settings simply get us as close to true picture as possible. So what causes all this?


It's in the DVD format, which was set when 4:3 TVs were still most common.

"Anamorphic transfers onto DVD horizontally squeeze the original widescreen image to store the information into a 4:3 aspect ratio DVD frame. If the TV has a feature to un-squeeze an anamorphic image, it will horizontally decompress the image to 16:9. If not, many DVD players can also reduce scan lines and add letterboxing bars above and below the image before sending it to the TV." - en.wikipedia.org – aspect ratio


Here's a page that describes this in more detail:
http://www.audioholics.com/education/display-formats-technology/understanding-widescreen-letterboxed-and-pan-scan"]http://www.audioholics.com/education/display-formats-technology/understanding-widescreen-letterboxed-and-pan-scan - I'll actively link this when I get to 3 posts and am able. =)

As this site says, "The DVD spec allowed the picture to be "pre-squished" into what we now call anamorphic (or sometimes dubbed "widescreen") video. Without processing, this condensed video would appear on a 4:3 television as if everyone were tall and skinny. DVD players, however, could take this content and stretch it back out to the correct aspect ratio and provide the black bars on top and bottom."


Basically, anamorphic DVDs intentionally squish the image horizontally, leaving it to the player and the TV to properly use the full encoding information to display the image on either a 4:3 or 16:9 TV.


Not all players and TVs will handle this the same. Your HDTV may have the same wide mode settings as mine or may not. If it does, your smart choice (for getting a proper aspect ratio and not making skinny people, etc.) is either Panoramic or Zoom 1. This will probably be a matter of personal preference. Panoramic leaves the center of the image skinny and expands the left and right sides more. Zoom 1 expands the image equally. Zoom 1 is probably the truest image but at times Panoramic seems crisper to me. I'll have to keep playing with it.


Some setups probably don't have the "4-bar" issue. But if yours does, hopefully this information helps. If your TV wide mode options are different, you may want to do some measuring. But the most important takeaway from this is that the more "stretched" modes are actually the right options, don't be scared by how different they are than the boxed mode which is actually very squished.


-S
 

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i only get the pillarbox on some movies, i fould out the movies were formatted ideally for 4:3 tv sets, so im gonna toss them out, or trade them and just get the Blue-Ray and watch them on my blue-ray player from now on. i know i still have my old aging DVD player but i dont have realy any more dvds im trying to move to blue ray.
 

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Discussion Starter · #3 ·
Yes, if the DVD specifically says: reformatted to fit your 4:3 screen those will definitely have pillarboxing.

Also, some of the earlier widescreen encodings were true "letterbox" meaning they coded in the black top and bottom bars. In that case the only thing you can do is deal with the 4 side box or do a full zoom.
 

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Quote:
Originally Posted by smares2 /forum/post/18262892


Yes, if the DVD specifically says: reformatted to fit your 4:3 screen those will definitely have pillarboxing.

Also, some of the earlier widescreen encodings were true "letterbox" meaning they coded in the black top and bottom bars. In that case the only thing you can do is deal with the 4 side box or do a full zoom.

I have an old essay here: Anamorphic vs 4:3 letterboxed DVDs .


-Bill
 
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