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Discussion Starter · #1 ·
Just got an FW900 24" Trinitron monitor . Before this, I watched HDTV on my Hipix through the 21" GDM-F500 . It's great to finally watch it on a wide monitor!


There are some interesting things I've noticed. For one thing, I was right about the Hipix dithering its output. It very definately uses dithering, and I suspect it dithers 16-bit colors to make 24-bit colors. I can very clearly see a checkboard pattern dithering at 1280x720p, regardless of the source of the signal. The moire I used to see at 1920x1080i on my F500 is all but completely invisible now on the FW900 -- but I can still see a miniscule hint of it in areas of solid color.


So, my question to the HiPix developers is, can it be reprogrammed to display 1280x720p in true 24-bit color? There's also a slight problem with 1920x1080i on the FW900. The top 20-30 scanlines are misaligned and wavey. Would it be possible to increase the vertical front porch in that mode via an option?


EDIT: I brought up the issue of dithering in this thread . I hope that my argument will carry more weight now that I'm using a higher-end display, because I'd really like the issue of dithering to be fixed or at least addressed.
 

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*Kind of wonders how you can complain with a monitor like that*
 

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Discussion Starter · #3 ·
Hehe, look at the label under my name. ;)


But seriously, I do love this monitor. I wasn't complaining about the monitor, though, I was complaining about the Hipix (which I also love). Go figure. :)
 

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Discussion Starter · #4 ·
For anybody who's interested, I just took a measurement of the exact aperture grill pitch of my new monitor. I displayed a pattern of alternating black and white vertical stripes one pixel thick, and adjusted the monitor's horizontal size control until there was no moire in a large area in the center. I measured the horizontal area that had no moire whatsoever, in millimeters and in pixels, and divided (216/900). Then I did the same thing for the outer edge, although it was a much smaller area there (23/85).


What I measured is that in the inside, the stripe pitch is exactly .240mm, and on the outer edge, it's .27mm. I'm pretty confident in my measurement techniques. So Sony pretty much lied by saying it was .23mm on the inside. Not that I mind :) I absolutely love this monitor. But it's an interesting fact.
 

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Make sure to try out the new 1360x768p mode that comes

with the HiPix 3.0 beta 2 softare. On film sourced

material it can look very nice.
 

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Thats peculiar - are you sure you installed the right driver

(and rebooted) before trying to run the HiPix 3 beta 2

software?


On my W900 I get a nice 48Khz signal with less

flicker than 1920x1080i. I can notice the slight

decrease in resolution, but in 14Mbit/sec HBO movies

scanned from 24fps film sources it looks better

because they really don't seem to have much more

than 1400x800 worth of resolution anyways.


True 1080i video recordings (like from PBS) deserve

real 1080i mode so that you can see all the detail.


By the way - I still don't notice the "dithering" you

talk about with the HiPix.


The scaled modes (less than 1080i) do show some

minor "scaling artifacts" (like extra jaggies on

completely straight diagonal lines) but they still

look like full colorspace (not "indexed" color)

to me.


I have seen some content which looks inherently

"dithered" all the time (even in 1080i mode) which

I attribute to the Telecine machine used to do the

film scan.


Do you see this "dithering" on all shows or only some?
 

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Discussion Starter · #8 ·
Thanks for the quick reply! :)


I think at some point my driver was reset back from Beta 2 to Beta 1. I'll try updating it later.


About the dithering -- I think you need a small stripe pitch to be able to see it. If I'm not mistaken, the W900 has a lower resolution than the FW900 (.25-.28mm spec as opposed to .23-.27mm).


And it shows up regardess of the broadcaster/source of signal. I always had moire at 1920x1080i on my GDM-F500 (easiest to see in solid areas), and I always saw some kind of strange pattern at 1280x720p that I couldn't quite make out. Now on my FW900 I can make it out clearly as checkerboard dithering, and it's always there (but easier to see in dark scenes -- according to my theory, that'd be because of the greater contrast between quantized 16-bit colors).
 

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Discussion Starter · #9 ·
Okay, I updated my driver to Beta 2, and that actually fixed another thing: 1920x1080i displays perfectly now! No waviness on the top scanlines. Very interesting -- what was changed between them that would fix that? Anyway, 1360x768 works fine, but I don't see why I'd want to use it, because DeinterlaceBeforeScaling doesn't recognize a pulldown. Good film-source 1920x1080i looks great to me in its native resolution. (BTW, why does DeinterlaceBefore Scaling work for 1080i sources but not 480i?)


(I can still see dithering at 1280x720, BTW).


Another edit: very interesting... just after saying that, I switched to a 480i channel and it's being deinterlaced with de-telecine! How come it happened for 480i, but not 1080i? And it's still random, not reproducable :( I switched to another channel and back, and now it's back to plain-old bob deinterlacing.
 

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Quibt,


As far as I can tell the hipix looks identical to my stb for playing HBO HD movies. One of Glimmie's test patterns should do the trick and will allow you to take a digital pic of your problem. (do a search if you are unfamilliar with the patterns.)


Good luck


-Mr. Wigggles
 

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Discussion Starter · #11 ·
MrWigggles,


The test patterns are no help, because they just have black and white and primary colors and stuff.


I am suspecting at this point that the pattern I'm seeing isn't dithering after all, but is a pattern of fine diagonal lines going from the upper left to the lower right. I have taken a picture of a 38.5mm*28.9mm area of my GDM-FW900 displaying output from the Hipix at 1280x720p. Not that it matters, but displayed is a freeze-frame of 720p source material (though the diagonal lines appear on everything, even signals upconverted and downconverted).


Who can spot the diagonal lines in this picture? It might help to stand far away from your monitor. If anyone would like to see the original 1600x1200 photo, please say so.
 

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I can't say for sure but I do sort-of notice some

diagonal artifacting when watching some HDTV but it is

very subtle and maybe it is just a side effect of the

MPEG2 encoding?


This may not be meaningful but one of the HiPix driver

developpers told me that the live video buffer was organized

in a funny staggered order... Not just a simple left

to right up to down X by Y sort of bitmap.


Anyways I don't find any of those artifacts

(perceived or imagined) enough to be an issue

for ~my~ watching enjoyment.
 

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BTW: I think I noticed the diagonal pattern when watching

a full frame of ocean from the air

(in particular parts of PBS Visions of Italy).

The combination of the motion of the waves and

the irregular pattern of the ocean made it easier

to see any sort of regular "line" pattern in the image.
 

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I've had a W900 for 4 years now, and it is by far the best money I have ever spent on any PC component. I highly recommend it to anybody...especially anyone considering purchasing a computer in the $2000+ range. Skimp on the PC and upgrade the monitor...you'll have it much longer.
 

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e vey:


Don't forget that the Sony w900 is also rebadged as an SGI GDM-90W11. Just picked one up on ebay for $799 - or about what you would pay for a passable 18" LCD.


...and I saw another (since sold) that was selling for $699 w/free shipping. If you want one, it's worth keeping an eye out on ebay.
 

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I've been salivating over this monitor for quite some time! It is nice to see some other 'perfectionists' are using it and really enjoy it. I've had a NEC Multisync 6FG and it's predecessor for many years without any problems, but over the last year or so I've really wanted to view a GDM W900 or the newer FW900.


Please post your impressions in greater detail on the monitor - or email me. I would love to hear more people say they love it because I've been saving and really want one!


Thanks, Brian
 

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Brian:


Still in the 'honeymoon' stage with mine. Haven't even had a chance to do any testing or custom resolutions. My GeForce3 card has a 1280x768 mode that I'm currently using and it's wonderful.


Monitor construction is tank-like - weighs 92lbs! Trinitron monitor is sharp as a tack, has NO moire problems, super color saturation, and the screen seems to go on forever... :)


If I had THREE thumbs, they'd all be pointing up...


If you're interested, I know a dealer in Oklahoma City who has about 50 of them in stock. His ebay price was $799 plus $50 shipping - not sure what an over-the-phone price might be. He describes their condition as 'near flawless' and that looks right to me.
 

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Jimmer2,


You have mail.


Brian
 
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