Pal plasma TVs... 480lines? 768 lines? WTF

[nielm]

Ok. so it looks like my living room TV has died ...

Which means I start looking around for alternatives, preferably with a VGA or DVI input...

I am in PAL-country where we have 576 lines (until HDTV arrives in about 500 years time), so why the hell do 90% of the LCD and plasma TVs have either 480 lines (!) or 768 lines(!!)

The last few years of playing with sage have taught me that any vertical video scaling can really mess up the image, unless you do some serious deinterlacing, which can also cause quality loss, so the above resolutions are usless for either SDTV or HDTV..

What more can I say but... WTF?!

[stanger89]

Originally Posted by nielm

Ok. so it looks like my living room TV has died ...

Which means I start looking around for alternatives, preferably with a VGA or DVI input...

I am in PAL-country where we have 576 lines (until HDTV arrives in about 500 years time), so why the hell do 90% of the LCD and plasma TVs have either 480 lines (!) or 768 lines(!!)

Best answer I can give? Probably because plasma's started out as business devices, hence a computer friendly 1024x768 or 1280x768 resolution. Then as the "thin is in" craze hit, and there appeared a market for cheaper options. The "EDTV"s followed. My guess is that the lack of "pal-res" Plasmas is due to the much higher production cost (retooling higher res) and final price vs a 480 pannel, and that most people willing to pay the extra would be the types going for the 720p capable displays.

The last few years of playing with sage have taught me that any vertical video scaling can really mess up the image, unless you do some serious deinterlacing, which can also cause quality loss, so the above resolutions are usless for either SDTV or HDTV..

Well, first off, you're going to have to do some "serious deinterlacing" with a plasma, or any fixed pixel display, because they are natively progressive. So you can't get the 480i to 480i (or 576i to 576i) video chain you can with an SDTV.

Second, I think your fears of scaling are unfounded. While based in fact (that 480i -> not 480i -> 480i is very bad) the 480i -> deinterlace -> not 480i is not a bad thing. A 768p pannel will work very well for you, as good or better than a theoretical 576p pannel. The problem (that you're thinking of) isn't with the deinterlacing/scaling, it's with the loss of field order basically, it's the not 480i -> 480i process.

What more can I say but... WTF?!

Get a 720p (768p) or 1080p display and be happy

[teknubic]

Are you locked into either LCD or Plasma? Have you considered anything else?
The InFocus ScreenPlay 5700 Projector does 576 native, is under $3K US, has both inputs you mentioned and has great reviews.

[nielm]

(a bit calmer now...)

Ok so 768p is not too bad for SDTV... and for sage playback it would be OK, but for 720p HDTV (if it ever comes)... do they leave 24 blank lines top+bottom, or try to scale up by 106.667% (ugh!)

I am not locked into plasma/lcd, but I am locked into 'box in the corner' so projectors are right out (14ft high ceilings don't help!)... I am hoping to find a nice HDTV-ready 100Hz 16x9 CRT ... Some hope... It's really flat screen or nothing here at the moment...

[stanger89]

Originally Posted by nielm

(a bit calmer now...)

Ok so 768p is not too bad for SDTV... and for sage playback it would be OK, but for 720p HDTV (if it ever comes)... do they leave 24 blank lines top+bottom, or try to scale up by 106.667% (ugh!)

Scaling, if done well, is not a bad thing, just see all the people who use upconverting DVD players. I think you're wrongly prejudiced against scaling based on your experience with SDTVs.

Scaling with HDTV is going to be a fact of life, since save a very few 75kHz capable CRTs that can display 720p and 1080i native, all HDTVs scale either 720p or 1080i (plus 480i/p).

There's always the 1080p route
http://product.samsung.com/cgi-bin/n...LR5078WX%2fXAA

I am not locked into plasma/lcd, but I am locked into 'box in the corner' so projectors are right out (14ft high ceilings don't help!)... I am hoping to find a nice HDTV-ready 100Hz 16x9 CRT ... Some hope... It's really flat screen or nothing here at the moment...

OK, so what is the 100Hz stuff I keep hearing about? I know it's unique to PAL-land. Is it just a TV with a "line doubler"?

Besides something like this:
http://www.pioneerelectronics.com/pn...etailComponent

Would be excellent for anything pretty much.

[nielm]

Thanks for calming me down re scaling I still don't get how they can try to sell 480 line TV's in a 576 line area...


100Hz is a way of reducing the flicker associated with large screen CRT's -- at PAL's 50 fields/sec, it is often possible to 'see' each frame (especially under certain lighting conditions)... 100Hz CRT's make the image more 'solid'

Ok, so that sounds like marketing-speak, but when I bought my now-dead TV, comparing 100Hz CRT's to standard CRTs, the image was clearer and more stable.

I believe that they work by refreshing each field twice...
Wikipedia Flicker-free/100hz page
Philips' How TV works page

Looking into it further, some TVs (mine included) perform some kind of interpolation to create intermediate frames, so that it actually creates 100 frames/sec...

Hotlined image from Philips' website:

taken from article on Philips' 100hz Natural Motion technology

[Lucas]

Originally Posted by nielm

(a bit calmer now..

I think that's warranted.....

It's not that bad really. I run concurrently a 576i PAL SDTV and a 480p LCD projector and I have a satisfactory arrangement.

In reality, the 768 displays are either 1024x768 with non square pixels(usually plasma) or 1366x768 (usually LCD).

Forgetting about HD video which currently in Europe is available only via the HD1&2 pan european sat channels and shortly via some pay-TV satellite services, the real challenge is in upscaling and deinterlacing SDTV PAL signals.

Either way, you get your new TV and then experiment. Send a 576p signal to the TV and let its scaler do the work or scale the signal in the PC and drive the TV via the Video Card(DVI) at its native resolution.

I suspect you will use the latter since I have yet to find a reasonably priced TV with better scaling and deinterlacing than the PC.

Make sure that the TV supports 50Hz @ its native resolution as well. Some only support 50Hz in PAL resolutions ie 768/720x576...... It is essential.

From my experience with a PAL signal, there's little difference with 480p(EDTV) and higher res(HD Ready) sets.

[stanger89]

Originally Posted by nielm

Thanks for calming me down re scaling I still don't get how they can try to sell 480 line TV's in a 576 line area...

From a manufacturing/cost standpoint I can kind of see, but yeah, it is a bit odd

100Hz is a way of reducing the flicker associated with large screen CRT's -- at PAL's 50 fields/sec, it is often possible to 'see' each frame (especially under certain lighting conditions)... 100Hz CRT's make the image more 'solid'

So it is just what we would have called a "Line Doubler".

Ok, so that sounds like marketing-speak, but when I bought my now-dead TV, comparing 100Hz CRT's to standard CRTs, the image was clearer and more stable.

Exactly the reason many/most of us insist on HDTVs for large screens

I believe that they work by refreshing each field twice...
Wikipedia Flicker-free/100hz page
Philips' How TV works page

Looking into it further, some TVs (mine included) perform some kind of interpolation to create intermediate frames, so that it actually creates 100 frames/sec...

Actually probably 50 frames per second (from 25) probably displayed as 100 interlaced fields per second (like our Mitsubishi that can do 960i)

Not that it will help (since it doesn't work with the Dshow filters) but you might want to look at WinDVD6/7 which have DNM.

[Kanati]

Scaling with HDTV is going to be a fact of life, since save a very few 75kHz capable CRTs that can display 720p and 1080i native, all HDTVs scale either 720p or 1080i (plus 480i/p).

And doubly so for PAL users...

And keep in mind that plasmas can and will burn-in if you show 4x3 pictures with black bars on the sides. You'll have to scale that to the full screen as well to avoid it... Besides the cost, that's one reason I went with a DLP setup. They and LCD's don't burn. (Well, they SAY they don't, but I've seen some questionable ghosting on a couple lcd screens that indicate otherwise).

As stanger said you'll want a 720p or 1080i capable screen instead of 480p only.