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I have a small side business authoring DVD for local bands (DTS, DD, 4:3, 16:9 etc). So I'm very knowledgeable on the authoring process. I don't own a projector so maybe someone can help me out with this question. What's the point running the resolution of the display higher than 720X480. All DVDs are encoded at that resolution.

Of course I'm speaking in terms of HTPC where one has the ability to change the displays resolution. Running the display higher than that just blows the picture up past it's native resolution?
 

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Because the native resolutions of the digital PJ is often much higher or at the very least not exactly 720x480, and scaling has to be done *somewhere* and it's generally good to have it done with a good standalone scaler of failing that a HTPC-- in general that will result in a better picture than using the PJ's internal scaler.
 

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I have wondered this same thing. If you are viewing dvd's only, doesnt seem like you need any more resolution than 720x480.


in focus x1 uses some cropping not scaling to turn an 800x600 res to a wide screen format. Could an xga projector get a better resolution by scaling into a bigger pixel grid? Doesn't seem like the difference would be noticible at all but I haven't seen them compared. So if you watch just dvds would an xga get you a better picture? Is it worth the extra cost? Hmmmmm.


I watch dvds so this seems the way to go as 800x600 res is much cheaper than xga but can someone comment on this? Pehaps if you want a really large screen, a scaled xga picture might turn out better because less screen door? Does it justify an extra 1000 bucks though?


Also another thing. Some people want to buy xga projectors because they also want to view hd tv. Hdtv will take more advantage of xga's greater pixel numbers. Sounds logical to get one for HDTV. HOWEVER- 1080i uses 1920x1080 pixes. That is WAY more than 4:3 xga can make. Am I missing something here? Doesn't seem like xga projectors are really going to satisfy for HDTV viewing.


In a year I bet for dlp projectors you will be able to get one with this native resolution for less than 3k. Personally, if I wanted to watch hdtv I would be bothered by losing so much resolution and would be inclined to wait on my purchase.


So, is xga worth it for just dvd and maybe some computer viewing?
 

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Don't forget that an anamorphic DVD when projected at 720 x 480 will mean that everybody will look tall and skinny.


To correct this, you'd have to remove lines of resolution if you were to stick with a width of 720. A better method of displaying would be to stretch the image sideways, keeping the full height resolution of 480, but now with a width of approx 853 which is a ratio of 16:9.


If a pj was 800 x 600 this would equate to 800 x 450, but with the loss of 30 lines of vertical resolution. You could overscan and keep the full height, but lose some of the image off the sides (26.5 pixels each side), so either method loses something.


If a pj was 1024 x 768, you'd have more than enough width to display full resolution but with some additional scaling, and this would work with PAL sources too, so in this case PAL may appear better/sharper than its NTSC equivalent (quality of authoring not withstanding) due to the higher resolution and no scaling - PAL is 1024 x 576 for a perfect 16:9 image with no lines added or taken away.


HTH


Gary.
 

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30 lines of loss doesn't justify an extra 1000 bucks I dont think.


Also where do you get that number for 1024 wide on PAL? I just looked at a site that showed PAL 1:85:1 at 720x544 and NTSC 720x461. A little cropping, here a little scaling there, doens't seem like you are going to lose a whole lot going svga. I'd like to see some side by side comparison reports on image quality.
 

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On a computer screen/widescreen set anamorphic DVD's have a much higher resolution. Just pop an anamorphic disk in the drive and see, it stretches much more to the sides. A non-anamorphic widescreen disk will look like an 4:3 box and have the 720x480 (720x576 PAL) resolution. If you set your monitor to this resolution it will exactly fill out the screen with no scaling requiered.


However if you use an anamorphic disk, the picture will resize to the 16:9 size and thus be wider than the screen can display (using the 4:3 resolutions given above). A more natural resolution for 16:9 would be 1024x768. At that size the screen will fit almost exactly to the width (it does fit exactly with PAL DVD's).
 

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Yes a more natural fit, but still you are only losing 30 scan lines and are still not taking full advantage of the 1024 width resolution. 720 will still have to scale up won't it? I don't know, doesnt justify 1000 bucks. So you are paying a lot more for just a little more quality.


There is a new disk that is coming out that can store I think 5x the dvd capacity. Won't be coming to the US anytime soon. They are trying it in Japan first because they are closer to going full HDTV. Then I would say you will have the full resolution to justify the extra bucks.
 

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Quote:
Originally posted by Mash
I have wondered this same thing. If you are viewing dvd's only, doesnt seem like you need any more resolution than 720x480.
There have been many posts on the >$5k forum in the past explaining how adding extra pixels will increase the image quality. Consider having double the number of pixels on the DVD in both the vertical and horizontal (1680x960). Even the dumbest scaler in the world could just display every pixel as 4 and you wouldn't see any advantage. However, put any intelligence at all in the scaler and it can make curves less jagged, etc.


There is some point at which adding extra lines won't make up for the fact that you need to scale the image, but from what I've seen a 1024x768 display will do better at showing DVDs than one that is closer to native resolution of the DVDs. I haven't done this experiment directly, but one way to try this is to display a DVD at 720x480 on a higher resolution display and then sit one times the image width away. Now go full screen and move back to one times the new image width away. I believe the higher resolution image will look better. There were quite a few discussions a while back about the AE200 doing a better job with DVDs than the AE300 (by people who hadn't seen them) because it could map them pixel-for-pixel at full screen. I had the AE300 and I thought DVDs looked better scaled to 960x540 than displayed pixel-for-pixel. Today's scalers are pretty good.


--Darin
 

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I have compared the NEC LT150 to the NEC LT75z. I own the lt150 and my brother-in-law recently purchased the lt75z. lt150 is 1024x768.....the lt75z is 800x600. I paid $2300 for my projector (new) last year. Upon viewing my setup, I corrupted my brother-in-law and he purchased the lt75z two months ago for around $1400 (new). We both own the Panasonic rp56 dvd player. Settings on projectors are similar and both are set to CINEMA. We can't see any difference between the two projectors when viewing a DVD. We showed both projectors, side by side, to friends and no one could see a difference. Well...actually everyone agreed that his projector was slightly brighter than mine (1000 lumens compared to my lt150's 800). :( Both projectors are only used for viewing DVD's so I suppose he made a smarter purchase and saved himself a grand. But I wouldn't trade my lt150 for anything. I use to have my HD receiver hooked up to the lt150 but I moved it upstairs. Now I view HD material on my 43" widescreen Hitachi RPTV in the livingroom. Not that the lt150 couldn't handle it, but the difference in PQ between the lt150 and the 43" Hitachi are like night and day but that's a whole other topic.


Herm
 

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IIRC, the LT150 needs an outboard scaler or HTPC to really do it any justice, just like my Davis DLS8 does.


If you use HTPC on both LT75 and LT150, then you may then notice a difference between them.


Gary.
 
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