Confused! HD & DVDs

[kevin_uk]

I have a Loewe Spheros 26" LCD HD television which is sold as a 'reference' quality set.
I was going to wait until HD DVDs were available before buying a DVD player to go with it, but have got fed up waiting as another format war seems imminent (and don't want to lose out again - I'm the other person who bought a Betamax video player years ago!) and have now decided to buy a standard DVD player so I can watch DVDs NOW!
I'm getting conflicting advice from high end hi-fi and video shops - am I better off connecting something like a Panasonic DVD player which has upscaling or a high quality standard player like the Arcam with just composite connections? I was heading towards upscaling but am now told an Arcam would give better results. Any views please?

[gordong11]

If your TV has either or both a DVI connector or HDMI connector...get an upsampling DVD player...but one that best suits your TV. for instance if you have DVI...get an oppo OPV971H...if you have an HDMI slot.....get just about any upsampling player. Also if your TV is a 1080p TV....get one that upsamples to 1080P, not just 1080i..ie Samsung DVD-HD960 or Oppo 981HD.

If you do not have an HDMI connector or a DVI Connector..then you can't upsample and not worth owning one that does.

Not all upsampling DVD players, upsample well enough to notice...thats why I's stick with Oppo...its the industry standard. IF 1080P, then I think the Samsung is a good call.

[edDV]

The Loewe Spheros 26 is a premium display that has a good video processor per the reviews. It has 1366x768 native resolution and at 26" size, you shouldn't notice much difference with a component vs. DVI connection. Larger, higher resolution displays will benefit from DVI/HDMI.

The display is essentially 720p native. It will receive either 720x480p from the progressive player and upscale in the TV or, you can buy an upscaling DVD player and feed it 720p over component or DVI. With upscaling, what is more important is the processing quality in the DVD player because it would be bypassing the rather expensive processing electronics that you purchased in the TV.

From progressive movie DVDs the processing load is light to get from 480p native DVD to 1366x768. For interlace 480i DVD discs, a 480i connection will use the deinterlacer in the TV. A 480p or 720p connection will use the deinterlacer in the DVD player. This forces the need for a premium quality DVD player. These issues are much more important than a 480p vs 720p connection if interlace discs are going to be played.

Even if all the DVD processing is going to be done in the DVD player, the TV deinterlacer will still be used for watching normal PAL sources for broadcast, VCR, camcorder, etc.

[bobkart]

I have a question, sort of related to the above discussion, for edDV (knower of all relating to video!).

Doesn't overscan ruin the nice pixel-perfect relationship between, say 1920x1080 content fed to a 1080p display via HDMI? Same question for a 480-line or 720-line fixed-pixel display, when fed 480i/p or 720p (respectively), with overscan don't you lose the benefit of an exact pixel-to-pixel match between the source signal and the display, meaning that the signal is somewhat upconverted anyway (5-10%)? Do they no longer overscan on HDMI sources perhaps? I am definitely seeing overscan via Component Video to my three HDTVs (two are fixed-pixel).

[jagabo]

with overscan don't you lose the benefit of an exact pixel-to-pixel match between the source signal and the display

I was wondering the same thing. Not to mention that the typical 720p display is something like 1366x768. So a 1280x720 source either has to be scaled up or output to a subset of the display.

[edDV]

As far as I know you are correct. There were a few 1280x720p displays but most were 1280x768 or 1366x768. So they would need to be scaled and overscanned from 1280x720. to the actual display.

I suppose but don't know the same goes for overscan on 1920x1080p displays.

BTW, normal DVD is never shown as 720x480 either. It gets horizontally compressed to 4:3 or expanded to 16:9 and then mapped to square pixel displays.

CRT comes closest to showing actual pixels at 480p but the scan needs to pass through the shadow mask pattern.

[bobkart]

Okay thanks for that information.

My first HDTV is 720x1280 by the way, A 52" Zenith rear-projection LCD.

And yeah I understand about the 720 across of 720x480 not mapping directly onto 720 pixels, it is sort of halfway between 4:3 (1.33:1) and 16:9 (1.78:1) at 3:2 (1.50:1).

So that information is a bit deflating in the sense of not really getting a perfect pixel-to-pixel match when sending "full HD" to a 1080i/p display over HDMI. I'll bet a lot of people out there think that's what they'll get (a'la DVI to a PC monitor). Seems like they could at least give you the option to turn off overscan. It seems to work this way if you are sending a PC signal to an HDTV.

[edDV]

It's a good subject to research.

[gshelley61]

These types of displays usually have a VGA input that generally does not apply overscan.

With TV signals, even HD programming, a little bit of overscan is desirable. Analog SD sources tend to have noise or black space around the frame edges, and you don't want to see that anyway.

With SD and HD digital signals, sometimes there can be some digital information noise on the top frame edge that, again, you don't want to see on the display.

Some Samsung DLP's have a way to shut off the overscan in the service menu. My Toshiba 62" 1080p DLP has 2.5% overscan, which is just right for my purposes. It fully resolves and displays a 1920x1080 resolution test pattern down to the single pixel level with no problem, as well.

[bobkart]

At 2.5% Overscan, every 40 pixels of source content (in either H or V directions) would be spread across 41 native pixels on the display. I realize it happens all the time, but it can be undesirable compared to a 40-pixel-to-40-pixel mapping. The middle pixel of those 41 on the screen is artificial, being made up of 50% of the color of the source pixels on each side of it. (And of course I understand that at the dot pitches we are talking about, this will go completely unnoticed in any kind of real-life video/film material.) Yeah, you can see every source pixel, and a few more that weren't really there, minus of course the missing ~52,000 pixels around the edge that the 2.5% percent overscan caused.

Anyway, it is what it is I guess. It just seems to defeat the purpose of digitally sending, pixel-for-pixel, a signal exactly matching the native resolution of the display, which the display could so simply just map straight onto its native pixels, only to have it upconverted by 2.5%, throwing all the "perfection" away. Could have done better perhaps with an 1872x 1052 native resolution display instead, and just lost the outer 2.5% of the pixels anyway, but had the retained 97.5% (in each direction) map straight onto the native display pixels.

Sorry for the slight rant. I guess now I am motivated to be sure any 1080p display I purchase has a way to turn off overscan.

[gshelley61]

At 2.5% Overscan, every 40 pixels of source content (in either H or V directions) would be spread across 41 native pixels on the display. (And of course I understand that at the dot pitches we are talking about, this will go completely unnoticed in any kind of real-life video/film material.)

And that really is the case. As I mentioned above, with the exception of some digital signals, there is often video noise, data noise or black masking at the frame edges anyway. Analog videotape, for example, has head switching noise covering a significant portion of the bottom frame edge. You don't want to see that.

However, you are right that for clean digital video signals that have image information all the way out to the frame edges, it would be nice to have an overscan defeat for true 1:1 pixel mapping.

[edDV]

I found a good article.
http://forum.ecoustics.com/bbs/messages/34579/122868.html

"The Upshot: It Depends"