Why the small "letterbox"

I've got a new Panasonic 42" Plasma 1080p. Players are Oppo 980, now 983.

I've tried several older DVD's. Some are so beautiful, with the 1080p upconverting, it's hard to imagine them being any better. The fill up the screen in "full size" mode and seem to work perfectly.

At least two movies do NOT fill up the whole screen in their "full size" mode. There is a letterbox, and it looks sharp and clear, but has black bars on sides and top and bottom. The movie uses probably 70% of the screen.

I can zoom it to full size and it retains the full image since it has the right proportions, BUT, when zoomed it loses that razor sharpness. In it's smaller letterbox size it looks pristine.

Even odder, the standard information at the beginning of the DVD, prior to the first menu, DOES fill up the full screen. It's only when I play the movie that it shrinks.

I've tried every combination of settings imaginable, on TV and DVD player.

Have you ever seen this happen?
Any idea why?

Hint: In the case of "Don Juan DeMarco", one movie where I have this problem, it's a double sided DVD where one side is 4:3 and the other side is letterbox. The 4:3 side behaves as you would expect 4:3 to behave (is it 4:3? I forget but you know what I mean). That is, it looks pristine but has bars on the side where material was cut away.

Playing the letterbox side literally delivers a smaller movie, but all the material of the original width. It's almost as if the DVD thinks I have an old 4:3 CRT and is trying to deliver me letterbox .....

Is that the answer - that some DVD's were designed to ONLY deliver widescreen on the assumption that the full size screen is 4:3?

I'm definitely telling the DVD player that my TV is full size (16:9?).

Look on the DVD case to see what aspect ratio the original film was filmed in. Your TV is 16X9 (1.77:1) aspect ratio. Some DVDs are 1.85:1 (close to 16X9) and some are 2.35:1 which will require black bars across the top and bottom in order to display the movie in it's native aspect ratio on a 16X9 set.


sounds like older dvd's which are not animorphic
I have been following the thread http://www.avsforum.com/avs-vb/showthread.php?t=1001832 over at avsforum on the new 983 and it seems that this is a known problem. Some movies are identified as 4:3 when they are widescreen causing the exact effect you are experiencing. Oppo has released a firmware update to help address this issue. If you go to oppo's website and click on the player then on support you will see on the right hand side the new update. Just burn it to a disk or usb thumb drive and follow the installation instructions. It is very easy to do.
ANIMORPHIC: Many early DVDs did not bother with a 'true' (anamorphic) screen. They assumed the movie would be played on a 4:3 screen and mastered the movie INCLUDING black bars top and bottom in a 4:3 format. So now, when you play those movies, you get the original widescreen movie WITH black bars top and bottom (as part of the original mastering! of that DVD) then your widescreen TV plays the movie as it sees it, as a 4:3 movie (even though it is a widescreen with 'built in' black bars top and bottom, which also use up a portion of the bits.) so the sides of the 16:9 screen also have bars like for any other 4:3 movie.
Nearly ALL movies now are mastered as "anamorphic" or the image is the entire dataset, no 'wasted' bits on black bars at all, And the player sends the image it gets, so full 16:9 and whatever black bars you get with a 2.35 movie are just 'blank' and not wasted image.
(Look up anamorphic in wikipedia)
As for the menus... I think they use a different 'system' to create them, and they usualy just 'fill up' the screen no matter what. (I think?)
PS: a few studios STILL do not tell you it is anamorphic (or "enhanced for 16:9 screens) same thing, even though the movie IS.
just another 2 cents, you may be surprised, blue-ray and hd dvds are often letterboxed because of the aspect ratios mentioned above or you lose some image data on both sides.
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Thanks for the responses. I'll make sure the firmware is up to date. The folks at Oppo got back to me (great responsiveness via email or phone BTW) and said that yeah some older DVDs that are not anamorphic will do that, it's unfortunate but normal. Sigh!