How do 16:9 and 4:3 videos display on a 2.35:1 screen? [Archive] - Audio & Video Forums

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bjornb17
05-21-2005, 09:59 AM
Hi everybody,

I couldnt find a specific answer to my question so i thought i'd ask.
This question might be a bit backwards from what you're used to answering.

In the next couple of years (when i move into a larger place), I'm thinking about buying a large 2.35:1 widescreen projection screen along with a decent projector.

My question is.... with a 2.35:1 screen, how to 16:9 and 4:3 videos display on it? Are there black bars on the left and right, or will they stretch and be taller than the screen?

edtyct
05-21-2005, 11:40 AM
Basically the trick is to get something like a square peg into a round hole. Your projector's (http:///#) native aspect ratio of 16:9, or 1.78:1, has to find a way to fit a picture into a 2.35:1 slot without spilling over the top and leaving dead space on the sides. This is called fixed height projection, because the point is to keep the height of the picture the same for every aspect ratio, as opposed to the reverse situation-- projecting a 2.35:1 picture onto a 1.78:1 screen--which leaves black bars at the top and bottom. The way to fix height in this scenario is to squeeze an image vertically, via a scaler either internal or external to the projector (#), and to place an anamorphic lens in front of the projector to stretch the squeezed image to the full width of the screen in the case of 2.35:1, or short of it for every other AR. Pillar bars on the sides can be masked as necessary with curtains or other devices. This technique appeals to people who find that making 2.35:1 smaller to accommodate a 16x9 screen is counterintuitive, reducing the intended impact. It also can bring an end to pixels wasted on black bars and provide a slightly brighter image.

I should add that AVS has a forum dedicated specifically to advocates of this strategy. They go into much greater detail.

Ed

bjornb17
05-21-2005, 12:47 PM
thanks a lot. im checking out those forums as we speak :) sounds like it may be a fun (and slightly frustrating) project :)

shokhead
05-21-2005, 01:47 PM
Which widescreen formate has the least BB's?

edtyct
05-21-2005, 02:10 PM
Shokhead, if you mean black bars, in a normal 16x9 widescreen (#) situation, 1.78:1 is a perfect match, with no bbs, but 1.85:1 is so close as to be almost perfect, particularly because of overscan in most cases. In bjornb's proposed case, the bbs that are on the top and bottom of a 16x9 screen showing an image at 2.35:1 are nonexistent, and the bars that would be present on the sides at other ratios can be made inconspicuous. Side bars aren't as intrusive, or diminishing, as a letterbox, and they can be masked more easily.

Ed

Lexmark3200
05-21-2005, 04:11 PM
EDT is correct; on MY Mitsubishi set, lower-aspect ratio films framed at say 1:78 or 1:85 fill the ENTIRE 55" widescreen because of overscan, or so I was told....but these lower-aspect ratio films, ESPECIALLY if they were ANAMORPHICALLY ENHANCED for 16X9 playback, were designed to fill a wide screen I believe. When you get into 2:35:1, there will be slight letterboxing on top and bottom of the image; this is normal.

What concerns me most is what happens when full frame (1:33) material is played back on 16X9 sets; on my 55" Mitsubishi, a full frame DVD fills the entire screen, but is this because the TV is internally "stretching" the full frame image to fill the sides of a widescreen display? I get no "fattening" or "distortion" of characters or images when I play back full screen DVDs on the widescreen display in STANDARD mode.....hmmmmmm......

cam
05-21-2005, 08:04 PM
EDT is correct; on MY Mitsubishi set, lower-aspect ratio films framed at say 1:78 or 1:85 fill the ENTIRE 55" widescreen because of overscan, or so I was told....but these lower-aspect ratio films, ESPECIALLY if they were ANAMORPHICALLY ENHANCED for 16X9 playback, were designed to fill a wide screen I believe. When you get into 2:35:1, there will be slight letterboxing on top and bottom of the image; this is normal.

What concerns me most is what happens when full frame (1:33) material is played back on 16X9 sets; on my 55" Mitsubishi, a full frame DVD fills the entire screen, but is this because the TV is internally "stretching" the full frame image to fill the sides of a widescreen display? I get no "fattening" or "distortion" of characters or images when I play back full screen DVDs on the widescreen display in STANDARD mode.....hmmmmmm......
Some TV's can mantain the center image and then start to stretch (fatten) at the sides. It can be effective since your eye is normally fixed to the center. You must have a button some where that would play a 1.33:1 normally on your 16:9 screen, which would then display bars to the side.

Lexmark3200
05-21-2005, 09:59 PM
Some TV's can mantain the center image and then start to stretch (fatten) at the sides. It can be effective since your eye is normally fixed to the center. You must have a button some where that would play a 1.33:1 normally on your 16:9 screen, which would then display bars to the side.

That must be what it is; that my eye is fixed on the center maintained image, as you say, and the set must be fattening the side edges of the fullscreen picture; as far as buttons go, the TV remains on STANDARD mode for almost all playback of DVDs, unless they arent anamorphic, which is when I use Mitsubishi's "EXPAND" mode which fills the letterboxing much better, yet shows flaws in the picture quality; in this day and age, we should unfortuately not have to deal with non anamorphic releases, but thanks to Buena Vista/Disney not re-visiting their old titles....well.....

But I guess this is what is happening, essentially, with the fullscreen DVDs on the widescreen set, that the center image is being maintained while the sides are being a bit fattened, although with my naked eye I cant really detect "much" fattening; thanks for clearing this up for me anyway.

shokhead
05-22-2005, 05:31 AM
That must be what it is; that my eye is fixed on the center maintained image, as you say, and the set must be fattening the side edges of the fullscreen picture; as far as buttons go, the TV remains on STANDARD mode for almost all playback of DVDs, unless they arent anamorphic, which is when I use Mitsubishi's "EXPAND" mode which fills the letterboxing much better, yet shows flaws in the picture quality; in this day and age, we should unfortuately not have to deal with non anamorphic releases, but thanks to Buena Vista/Disney not re-visiting their old titles....well.....

But I guess this is what is happening, essentially, with the fullscreen DVDs on the widescreen set, that the center image is being maintained while the sides are being a bit fattened, although with my naked eye I cant really detect "much" fattening; thanks for clearing this up for me anyway.

Thats what my Sony does,i think its called the wide mode. I keep it on that and your right about the sides.

Lexmark3200
05-22-2005, 10:00 PM
Thats what my Sony does,i think its called the wide mode. I keep it on that and your right about the sides.

Well, on my Mitsubishi's STANDARD mode, which is what I leave it on because it plays back everything as it should in this mode, when I play full screen DVDs, they fill this entire 55" screen....I guess our TV's just stretch the sides a bit on full screen discs to better fill in the screen.....