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The InFocus X-1 and NEC LT-240/60 are among the recent well-reviewed and well-regarded 4:3 projectors which have a 16:9 "mode." Unfortunately, neither owners manual explains exactly what the projector is "doing" when you select this mode. Is the X-1 simply cropping 75 rows of pixels from the top and bottom of the image and then scaling the input signal to the remaining 450 lines? Is the NEC doing the same thing but with 96 rows off the top and bottom? Could someone who actually knows please enlighten me?
 

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Nope, not at all. Any DVD that is labelled "16:9 enhanced" or "anamorphic", has had the widescreen image stretched vertically, exactly 1/3 more, in order to take advantage of extra resolution.


In other words, all 480 lines of resolution are used to store the image. If it wasn't anamorphic, it would only be using 360 lines to store the exact same image (ie 120 LESS lines used).


In order to display the image correctly again, there are 2 choices.


1. Set the DVD player to "4:3 letter" for the video settings. This will actually cause the DVD player to remove every 4th line of resolution in order to make the image appear in the correct aspect ratio, and then it adds 60 lines of black to the top, and 60 lines of black to the bottom. Obviously not ideal !!!


2. Set the DVD player to "16:9". This will send the image, as is, to the display device. It appears stretched vertically, but contains all 480 lines. When you set the projector to "16:9", it then knows to scale the image and display it in the correct aspect ratio. However, since the projector is working "digitally", and is not limited to 480 lines, it doesn't need to drop lines out of the image as a part of this process.


Therefore, set the DVD player to "16:9", set the projector to "16:9", and you will be getting the best image you can.
 

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Dave,


The X1 does just what he says and drops lines off the top and bottom. This is in order to attain a 1:1 pixel mapping.


While your definition is reasonably comprehensive, it doesn't answer the question perfectly. The X1 takes a rather novel approach. What most projectors do when presented with more information than their panels is downscale it or try to come up with a representation of it at a lower resolution. This effects smooths out the picture and causes some detail to be lost.
 

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Just a question that I hope is related! When viewing a 16:9 signal, is there going to be light spillage when using a 4:3 native projector.


I recently used a Proxima X350 DLP projector, and it seemed the way it handled this was rather sloppy.


It seemed like there was 3 bands of light projected. One for the image, one for the widescreen bars and a really annoying light border around the black bars.


Is this going to be the case with all 4:3 native projectors?


Thanks for any help!


Daniel I
 

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I think it would be safe to say that all 4:3 projectors will have light spill on a 16:9 screen . You can deal with that by installing masking around your screen to absorb and hide it. Black fabrics seem to work the best, and can actually enhance the overall "theater" look to your room.


Kevin
 

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Quote:
Originally posted by Namlemez
Dave,


The X1 does just what he says and drops lines off the top and bottom. This is in order to attain a 1:1 pixel mapping.


While your definition is reasonably comprehensive, it doesn't answer the question perfectly. The X1 takes a rather novel approach. What most projectors do when presented with more information than their panels is downscale it or try to come up with a representation of it at a lower resolution. This effects smooths out the picture and causes some detail to be lost.
From others experience I've read in threads, that seems to be the case, at least for the vertical resolution. The horizontal still needs to be scaled, so it isn't quite 1:1 pixel mapping.


Of course, this also only works for NTSC. With PAL source, it would definitely have to scale down the vertical resolution.
 

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Quote:
Originally posted by gks
I think it would be safe to say that all 4:3 projectors will have light spill on a 16:9 screen . You can deal with that by installing masking around your screen to absorb and hide it. Black fabrics seem to work the best, and can actually enhance the overall "theater" look to your room.


Kevin
Since that vast majority of movies, particularly new releases, are even wider then 16:9, you will get light spill on just about any projector. The only one, and I haven't seen it working yet, that is reported to totally eliminate this problem regardless of aspect ratio, is the NEC HT1000. It uses internal masking of unused pixels, so no light spill at all.
 

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AHH I very true! Even 2.35 movies I suppose will have the bars and surrounding light on a 16:9 projector. It makes sense. Does the fabric do a really good job of masking this? It was really distracting to me.


BTW thanks for the help guys!


Daniel I
 

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One thing that can be done with a 4x3 projector if you're buying a pull-down screen is to just order the 4x3 screen and have them mask it to 16x9. That is what I've done for one of my screens. Yes, on the M20x the menus do end up on the black, but are still generally readable. Nobody really knows that there is light spill on 16x9 material since it is projecting gray onto the black part of the screen. For me this is my 116" wide screen that I have in my living room, so for 4x3 material I just move the projector closer to the screen and use the center 4x3 part of the 16x9 image area. This works well for IMAX movies that tend to be a little lower quality that good DVDs and HD material. I'm thinking of ordering a 16x9 masked Hi-Power for my theater room and just using 2 screens in there. I'll either hang both or just quickly swap them if necessary.


--Darin
 

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Hi All,

As an aside: I have an LT150z and a DTC100. To watch 16:9 material (HDNet, for example), I use a combination of the STB set to 16:9 and the PJ set to 'Cinema', which gives me the proper aspect ratio without any bars (black all around). I guess I thought you always had to adjust something with the STB to get aspect right. No? Thanks. HNick
 

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How about subtitle? How is it handled? Just overlay the video image or have to sequeeze the image to make room?


Thanks
 

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Quote:
Originally posted by Daniel I
Just a question that I hope is related! When viewing a 16:9 signal, is there going to be light spillage when using a 4:3 native projector.


I recently used a Proxima X350 DLP projector, and it seemed the way it handled this was rather sloppy.


It seemed like there was 3 bands of light projected. One for the image, one for the widescreen bars and a really annoying light border around the black bars.


Is this going to be the case with all 4:3 native projectors?
Any 4:3 projector is going to project the entire 4:3 frame, so if you are watching 16:9 content there will be black letterbox bars projected above and below the image. Many data-grade projectors also have an additional halo of light spill that can be seen around the outside of the 4:3 frame.


NEC seems to have finally eliminated this halo with their latest batch of projectors. I have an LT-240 and there is no halo at all, just the letterbox bars.
 

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Quote:
Originally posted by darinp
One thing that can be done with a 4x3 projector if you're buying a pull-down screen is to just order the 4x3 screen and have them mask it to 16x9. That is what I've done for one of my screens. Yes, on the M20x the menus do end up on the black, but are still generally readable. Nobody really knows that there is light spill on 16x9 material since it is projecting gray onto the black part of the screen. For me this is my 116" wide screen that I have in my living room, so for 4x3 material I just move the projector closer to the screen and use the center 4x3 part of the 16x9 image area. This works well for IMAX movies that tend to be a little lower quality that good DVDs and HD material.
Darin, is the masking at all adjustable or is it permanently fixed? Personally, I choose to watch Imax movies using the whole 4:3 frame because it just doesn't seem right for them to be smaller than regular movie content. I like the idea of masking, but I would like to be able to remove it under certain circumstances. Is that at all possible, or am I out of luck?
 

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I think what he is sayin is that the masking is painted on the screen at the factory.


ddog!
 

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Quote:
Originally posted by ddog
I think what he is sayin is that the masking is painted on the screen at the factory.
Ah, well then, that answers that.
 

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Quote:
Originally posted by ddog
I think what he is sayin is that the masking is painted on the screen at the factory.
Sorry. Yes, this is pretty much what I meant. Painting is one way, but I also have a screen where they put the seams at the top and bottom of the 16x9 image area and have black material above and below. Either way, ti does preclude removing the masking.


I enjoyed using the whole 4x3 screen for IMAX movies at first, since they pretty much fill my wall from top to bottom. I still do that sometimes, but these tend to have lower image quality than 16x9 material, so it is really a tradeoff between size and quality. Since I have more than one screen I can choose what I want to do.


--Darin
 
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