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Discussion Starter · #1 ·
I successfully got 1080p on my nokia monitor at 60hz but why is it that when I connect to the projector it does not sync. Am I doing something wrong or is it impossible to do 1080p at 60hz on the 6pg extra.
 

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Discussion Starter · #3 ·
I figure since I am able to resolve 1080 lines I may as well see what it looks like at 1080p.


Running the Nokia resolution pattern I am able to see the scan lines at 1080i. I see a better picture at 1080i than 720p under windows 98. Since windows 2000 does not do interlaced overlay I want to do 1080p instead and see what it looks like.


I got 1920x720p and it looks decent but can't get 1920x1080p
 

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Try a different sync polarity.


Marc
 

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Discussion Starter · #5 ·
What do you mean by that. It is positive on both horizontal and vertical. Should I make it negative on both or which one?
 

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Even if you could, I thought that converting 1080i HDTV to 1080p was something a PC couldn't do in real time? I don't know why because in theory it seems like it would be no problem, but I swear I saw a thread once recently where someone who knows what they are talking about (Tim Martin, I think) said something to the effect of generating 1080p was an expensive proposition because the scalers that can actually do it are $$$...
 

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Discussion Starter · #7 ·
I'm not converting hdtv. I am scaling dvd playback to 1080p.


I got it to sync finally but I had to lower the refresh rate to 40 and the scan rate to 45 . It looked great but the flicker was awful due to the low refresh. What I fail to understand is the relationship between refresh rate and scan rate as it pertains to the pj. I thought as long as the refresh rate was withing the pj specs then it could sync a signal. Am I wrong?
 

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height x width x refresh x 105% = scan rate or "bandwidth" (forget which)


6pg/9pg can't resolve even 960p, 1080p will never look good.
 

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Discussion Starter · #9 ·
If you can resolve 1080i does it not mean you would be able to resolve 1080p? I can see the scan lines with no overlap at 1080i. I have not counted the lines personally but from the top to the bottom of the screen I see no overlap.
 

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because 1080i is 540 X 2 spread over 2 frames. it's actually drawing 540 lines on each sweep. Not 1080.




thinking about this - I suppose you know that - and chances are you are thinking that you are seeing the scan lines across 2 frames and therefore seeing all 1080, right?
 

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Discussion Starter · #11 ·
Well I see alternating black and white lines. Whether they get displayed over 2 frames is not as important to me as the fact that I can see all of the lines I am supposed to.


To me being able to resolve the resolution means I can see all 1080 lines. Now I know internal components may limit the projector to not being able to do all of them in 1 full sweep as progressive would mandate (it is not fast enough).


So when people say this pj cannot resolve 1080 lines maybe they should say it is not fast enough to display 1080 lines progressively. I could be way off base here but I see what I see.
 

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If I remember correctly, the 6PG Xtra may not have the bandwidth to handle 1080P.
 

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The 6PG extra will run fine with 1920 x 1080 @ 48 Hz, don't try to give it 60Hz, though, that's too much of a good thing for the 6PG's.


If you have to run 60Hz and want very little scan line structure something like 1440 x 810 is more appropriate. When set up properly and with maximized raster the 6PG extra will have a slight scan line structure still visible in the center at 1600 x 900 on a 16:9 screen, but this is with your nose almost on the screen ;)


Oliver Klohs
 

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Discussion Starter · #14 ·
My nose is almost at the screen right now. I am tuning today as you can tell. I will try 1440x810. Its funny how some argue it will never resolve 1080i but some prove them wrong.
 

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Even if you had enough bandwith you could never resolve 1080p with that projector. Only the best 9" CRT's are capable of resolving 1080p.


Remember that 1080i is resolved just as easily as 540p, at least as far as vertical resolution is concerned.


It all has to do with beam-spot size and scan line overlap. If you could somehow display 1080p, the scanlines are going to overlap so much that most would consider it unwatchable.


If you want to watch 1080p, you will need something along the lines of a Sony G90 or a Marquee 9500. A Sony 1292 might be able to pull it off as well, but I am not as sure.


Cheers


Andrew B.
 

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Andrew,


your statement that 1080p on such a machine is not watchable because of scanline overlap simply is not true. As there is only a maximum resolution of 720 by 480 pixels on a DVD you can even have, say 20% overlap and still see every bit of detail there is in the DVD signal.


I run an NEC 9PG plus I had for some time with 1920 x 1080p @ 48 Hz and it looked stunning. I also compared this resolution to others that were not as high and with DVD's you surely couldn't say that there was any loss of detail or perceived sharpness compared to 1280 x 720 for example.


Oliver Klohs
 

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Discussion Starter · #18 ·
Quote:
Remember that 1080i is resolved just as easily as 540p, at least as far as vertical resolution is concerned.
If we only look at vertical resolution you are saying that 1080i is easy to resolve. This displays odd/even lines in 2 frames and with your eyeballs you see all 1080 lines correct? If you change to 1080p why would you not see all 1080 lines if the projector just demonstrated that it can let you see all lines in interlaced mode. I mean if you could hypothetically pause frame 1 and pause frame 2 and put them together would you not see 1080 lines as 1 frame?


I am in need of understanding.
 

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At 1080i, it is not displaying all 1080 lines. The projector did not dmonstrate this at all. It is only displaying half of them at any given time. That's the definition of interlaced. It does all the odd, then the even. Hence 540 lines at any given time. That's why 540p can be displayed as easily as 1080i.


When you try to do 1080p, you are trying to display all 1080 lines at once. This is what the projector may not be able to do.


I can't answer what it can/can't do, only that you seem confused in your definitions of interlaced versus progressive.


Have fun!
 
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