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Ok, I have a NEC XG110 pj that I am currently running at 1080i. My questions is what do people think is better, 1080i or 720P? And why? I don't have my PJ set up for 720P yet but before I spend the time setting it up I guess I want to know why more and more people are running 720P over 1080i?


Rick
 

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Well, if we are talking about HD as being the source, I would run the native resolution of the signal. Just about all of that is 1080I. If we are talking about scaling DVD's than I would say 720P.


Chip S.
 

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I would also recommend running all HD as native rate. For DVD, I would recommend 720p over 1080i. Also, see if you can change the refresh rate to 72Hz for DVD, as that will eliminate judder.
 

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I'm bored and stuck at work so I've got time to explain it in detail.


Like these guys say, native is best. When converting 1080i to 720p, you lose resolution and is generally not worth it. Converting 720p to 1080i interlaces it for no reason other than to duplicate existing pixels, which also is not worth the downside. That goes for DVDs as well. 960p is the best for DVDs scaling-wise, because it's exactly 2x 480p, but if the projector can't resolve that w/o overlap (I hear the XG110 can though, but only with an expert pro setup), most prefer a sharper looking 720p.


Many people in AVSforum like to point out the fact that 1080i is the same scan rate as 540p. Some people are misled and think that means they're the same thing. Others know the that there's a major difference, but point it out anyways because they're fans of 720p, which causes newbie confusion and creates more people of the former group. Also, good advice often given for people w/ 1080i RPTVs is to run their HTPCs at 540p. This is a very good idea for reasons I mentioned, but I think it confuses a lot of people into thinking 540p and 1080i are the same thing. Point is, 540p is still half the resolution of 1080i, and don't let anyone tell you different.


Others will also point out that 1080i broadcast is filtered and your really recieving 1440x810 or so, and therefore you might as well run everything at 720p. However, they seem to fail in realizing that your decoder still sees it as 1920x1080, and it doesn't know which of the 907,200 pixels were filtered out, so if you downscale it, your losing even more. Now when it gets converted to analog to output to your projector, more pixel information is lost in that process. On top of all that, no CRT projector can resolve fully 1920, and few can resolve 1080 in 16:9 mode. Point is, I believe it's best to run 1080i at 1080i because your losing so much pixel information already, you won't want to add to that.


Anyways, using interlaced video is not worth it if your just duplicating pixels/lines.

Do a 720p setup and use if for all non-1080i source material. It's worth it. Later on in life, you can try 800p-960p setups and see what you like best for DVDs, which is what I'll be doing this month w/ my XG110 as soon as I finish my hushbox.
 

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Hi,


I've tested with my XG 1100 and Sony 7700 PSM1 combo exhaustively all progressive options 540p ,720p,960p etc.

However the best picture {depth,detail/resolution,colors,etc} i get is with 1080i, with barely no scan lines visible,absolute not to compare in pq. with 540p ;720p seems to be the best progressive option if you want it in that mode perse.

In my {proper} setup 1080i wins.


good luck,


CBT
 

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I think 1080i is a terrible choice for 480i/480p materiel. Why not just use 960i?
 

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Hi,


Bored again?


More context please.

Why is 1080i so terrible?,it looks like i said superb.

That's for me The reason,no matter what the specs say.

Maybe for some htpc and projector combo's it might work better

But then again maybe you like a softer image?{matter of taste}

Even more important ,did you tried it actually on a Sony 7700 psm 1 + NEC XG 110?


CBT
 

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Sony 7700 psm1? What's that, a video processor? Heh, won't find one of those at my home. Powerstrip is only $30.


Yes I have tried DVDs @ 1080i. It doesn't look very good. I haven't tried 960i because I find no reason to interlace a progressive video source when I don't have to. I only tried 1080i cause I set it up for 1080i HD materiel. But I can promise you that 960i would look better.


960 is exactly 2x the resolution of a DVD. Perfect scaling. I don't need to see for myself to know that scaling it 2.25 times original size is far from ideal. I mean, the difference between 960i and 1080i is so small, why on earth would you want a screwed up scale? And why not 1050i, or 1090i? I mean, there's nothing magical about the number 1080. Just cause it's an HD standard doesn't mean a thing when it comes to viewing DVDs on a CRT that can sync to anything.


I'm assuming that your 7700, whatever it is, only does standard HD resolutions, so you don't have a choice. The only other logical reason I can fathom for what your doing is that you don't want to spend the time setting up another signal, or you don't want it switching between multiple signal entries for whatever reason. That's fine, I have no problem if that's what your deal is, but as far as PQ goes, there is absolutely nothing good about DVDs @1080i whatsoever unless you have an RPTV or something that will only sync to 1080i. And even most RPTVs now will convert 480i/p materiel to 960i.
 

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I guess the simplest way to explain it is to say that the cleanest signal is native. the cleanest way to up-scale is in equal increments. From 480I the logical step up and the only other alternative available for quite a while was to deinterlace and go to progressive (line double 480P). As projectors got better and technology improved, triple (720P) and quadrouple (960P) came about. Not to long from there scalers became available with multiple resolutions and refreash rates. As a rule, the less a processor has to do, the less artifacts are produced. Scaling 480I to 1080P requires a great deal of processing where 1080I (HD) to 1080P is an easy job for a high end processor. Anything in the middle just makes things that much harder to deal with. And thats all I'm gonna say about that...


Chip S.
 

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Actually 720p, is not ideal either. True, the amount of scanlines are being tripled, but the frame is being scaled at 1.5x, which is unideal. Sure, it's easy on a processor and will help cut costs if your making and selling video processors or STBs, but the problem for users is uneven linearity. Doubling and quadrupling are the only ideal methods when going from interlaced to progressive or vice-versa. Everything else, including tripling, means that some pixels are being duplicated more than others. Tripling is fine when going from interlaced to interlaced, or progressive to progressive (i.e. 480i to 1440i), because your scaling it to a whole number. Multiplying interlaced fields by 3 is not ideal.


While both 720p and 1080i are unideal ways to scale DVDs, 1080i is interlaced, which to me and most, is not worth the benefits of upscaling a lower res source to a higher resolution, and why I think 720p is better for any source that has a 1280x720 frame or lower. If I didn't feel that way, and I liked 1080i better for DVDs, I'd might as well just use 960i so that it's scaled properly and I don't have to worry about it.
 

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Lifter you're assuming too much.

Sony dvps 7700 +psm1 ? try the search mode,it was all over this forum for years,bettered most htpc's in pq.

Do you actually watch dvd's; on other equipment then your own?,you keep doubling/tripling/quadrupling ... yourself about the specs.

No matter what technology is used,the proof remains in the pudding{concept}..

It's easy to keep this issue going on for ever with your technical assumptions /statements and frankly said quite boring.

It's much more interesting to compare equipment,and share your experience with this forum,and then" try" to analyze why maybe technology A{product} looks/is better then B.


So do try,instead of forcing always having the last word .

But then again.. these are all assumptions.


CBT
 

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So it's an NTSC DVD player. Lovely. Wouldn't it have been pertinent to mention what your using to scale it to 1080i? That is unless I missed something and it outputs 1080i (the AVS search is down right now, I had to Google it and got little results).


I didn't want this to turn into an HTPC vs. non-HTPC equipment argument. I'm sure you've been down that road before and you seem pretty defensive about it. I could care less and for all I know your setup could be absolutely stunning and blows mine to shreds (though I highly doubt it). It doesn't matter and it's besides the point.


What I pointed out was nothing short of basic multiplication. If you have qualms with things like reality, that's fine. I know plenty of people who stick by what they have and what they do regardless of all logic, and if I wanted to argue with those types I'd go into the $20k and up forum and do it.


I just find it funny how personal and defensive people get over their electronic equipment of choice. A reasonable response would be "Yes, your absolutely right, 960i would be preferable to 1080i in a vacuum, and that there is nothing special about 1080i except that it works with limmited-sync CRT RPTVs. But because of that, my equipment wasn't designed to allow 960i and I don't care because it looks great and I have no reason to change it. Furthermore, I doubt I or anyone else would notice an improvement."


What's wrong with saying that? Do you honestly disagree with it? Do you honestly think that with all things being equal (same equipment) 960i is not preferable?


But instead there's the typical "Doubling, Shmuboling. Your just talking about specs which is meaningless. All that matters is what (I think) looks best to me" response.


"Did you actually try it on a Sony dvps 7700 psm1?"


No. Did you actually try 960i on your Sony dvps 7700 psm1 and compare it to your 1080i? No. So we're in the same boat. Let's not go there.


I'm sorry if I'm acting like a jerk. I truly am. I can't help it sometimes (I'm not like this in person). I respect everyone's opinion as long as they recognize that it is nothing more than that- an opinion. I gladly admit that my preference of DVDs at 720p vs. 1080i is just an opinion. However, the fact that neither of those is an ideal way to scale 480i/p, and that 960i is an ideal way, is absolutely nothing short of a fact. When people start confusing opinions with facts, I get very annoyed.
 

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BTW, I think my attitude in this thread, as well as others, needs an explanation. I work at a small post house. I have a handful of co-workers, and they are self-dubbed "creative" types who are very ignorant when it comes to technology. But when it comes to purchasing and running equipment, they suddenly feel they are experts. They studied arts in college, not science. These guys think that re-using a digital betacam tape will hinder the quality so they waste tons of money on new tapes all the time. They think that an SDI interface needs a special SDI cable, and that a "regular" coax cable will hinder the quality. They think that hisses and hums that exist in the analog audio monitoring equipment will show up on digital to digital dubs, so they turn it all off before mastering tapes. They think turning their mixers and decks on and off everyday will lengthen the machines' lives, not shorten them.


This is the stuff I have to put up with everyday. Nobody wants to work with an a-hole, and I like these guys, so I don't give them them nearly as much crap they deserve. Plus, it's not my money they're wasting so I shouldn't care. But it still drives me nuts, so when I'm on AVSforum I often have unreleased aggression and it probably shows. So if I come off like an obsessive jerk, just try and understand where I'm coming from.
 

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I have a PSM1 inside my DirecTiVo. I will say that the Immersive H3D gave me a better picture, though I was having to deinterlace a lot of video sources and the DCDi was the clincher there.


My DirecTiVo HAS got 960p as an output resolution (1440x960p), along with 720p, 1080i and a handful of other resolutions and I will probably do some sort of comparison against the other resolutions some day, but I have too many more pressing matters right now.


I wouldn't say that the PSM-1 beats the HTPC being fed SDI, though, as long as you are outputting with a Radeon or using the H3DII.
 
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