TV Quality in Shops v Home

I recently bought a Panasonic 42 inch HD Plasma. When I saw it at Hardly Normals, they run this demo through it. HD Tv some really nice scenery shots from all over the world, Sand Dunes, beaches ect ect, its a standard demo that most shops use. Its crystal clear, very sharp image. But with my Plasma, DVDs are not a sharp, no where near it, why ? Cheers, Zach

Reply to
Zach
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The simple answer is - DVD ain't hi def - no where near it. Get a HD digital tuner, or a HD blueray player, or a HD DVD player, or a HD PVR - i think you get the picture now...

Reply to
Doug Jewell

DVDs are not as sharp.

geoff

Reply to
Geoff

Standard definition material (e.g. from a DVD) can look good but often isn't especially on most HD panels. Full HD (1080i or 1080p) on a 1920 x 1080 panel can look absolutely glorious. The 7 network HD demo loop (when transmitted in 1080i) can easily demonstrate this, and this is probably what you've seen in the shops. SD transmissions are 576i whereas HD transmissions are either 720p or 1080i.

Your Panasonic plasma panel has a native resolution of 1024 x 768 pixels (IMHO somewhere between SD and true HD).

The problem with getting a good SD picture on an HD display is -

1) The quality of the original SD source (DVD or transmission). If the available bandwidth is too restricted or the material poorly encoded you can get digital artefacts (blockiness or pixel crawl) especially around moving objects. I've seen pretty good SD transmissions but then again seen a lot of poor ones as well. Viewing a poor SD transmission or source does tend to look worse on a HD panel rather than on an SD panel.

2) The "engine" driving the panel. With an SD transmission or source the overall pixel count is less than the panel can display mapping at a 1 : 1 ratio, therefore to map the other "missing" pixels to the panel's native resolution, the "engine" has to guess or interpolate the missing information to map the picture to the panel. Depending on the capability of the engine driving the panel the resultant SD picture can look quite acceptable or just plain awful.

3) Viewing distance. Don't sit too close to the screen. You will notice the imperfections in the PQ much more if your viewing distance is too close. There is some good info about this on the dtvforum at -
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Cheers, Alan

Reply to
Alan Rutlidge

There are several reasons:

1) DVD's are a PAL resolution (720x576 pixels) source, not a hi- definition source. This standard def signal must be up-converted to display on your 768 or 1080 line hi-def screen.

2) DVD's vary *greatly* in picture quality. Some are absolute garbage with all sorts of film and conversion artifacts etc. Even a Blueray or HDDVD disc can be crap quality and not as good an image as the standard DVD version. It's all about how much effort the producer puts in to the conversion process. The best DVD's are usually the "ultimate editions" that have been digitally restored frame-by-frame etc, and especially movies which were filmed entirely in digital. e.g. the latest Star Wars movies and animated features etc.

If you want a demo of what your screen can do, there is a hi-def demo channel available on digital TV. Tune that in and enjoy the 10minute scenery loop.

Dave.

Reply to
David L. Jones

its to do with source material, connection type, picture settings and screen ability

source material: the quality of the program you are watching is one of the big factors, disney dvd's are usually the best quality reproductions availalbe. many are THX certified complete with a thx optimiser program on the disc.

quality goes from excellent (7hd loop) to good (disney dvd) to poor (foxtel) even a pgood analogue signal will surpass foxtel in quality.

Connection type: use atleast s-video when connecting sources but where possible use component or rgb/s. with analogue video connections, the more seperating of the signals the clearer the image.

component is the most common of the high quality connections, appering on many digital decoders, dvd's, PC's.

there is rgb/hv using the VGA connection but this is rare on anything but high def tuners etc.

Picture settings: configuring your contrast/brightess/sharpness etc settings to the right levels can make all the difference. get a THX dvd like disney's the lion king and use the optomiser.

contrast and sharpness are the big ones. turn off all image inhancers in the menu, all colour brightners, edge enhancers, black levels etc. try and make the image as natural as possible, many displays are set to look bright and colourfull for display purposes so they stand out in a store, however, these settings are unrealistic for general use and can distort the images naturalness to the point of annoyance.

screen ability: the scaler and panel driver are usually to blame when a usually good source looks crap. digital panels, especially high res units have a hard time when 1:1 or 1:2 scaling can not be achieved. the image usually suffers from double ups of sharp edges or missing eliments. either use a native res between devices or use an external scaler such as the one in the panasonic hdtv tuners.

the panel driver can make or break the screen. a good driver will allow good colour representation (8bit/pixel or 16.7mil colours) a poor driver usually falls to 6bit or 252thou colours. with plasma panels using PWM to shade (strobing the pixel instead of dimming) the speed of the driver usually is a limitation.

Reply to
matt2 - amstereo

Reply to
Zach

messagenews: snipped-for-privacy@i38g2000prf.googlegroups.com...

I'm talking about free-to-air digital TV, the one that will eventually replace the analog system. See this site for details:

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Channel 7 broadcast a high definition "demo" channel, you should find it (if you can receive the signal) if you scan all the channels with your digital set-top-box.

Many TV's now come with a digital decoder built-in, your new Plasma might even have one? otherwise you need a HD digital "set top box" and they cost about $100 upwards.

Foxtel digital is an entirely different and private pay-per-use cable service. When people talk about Digital TV, they do *not* mean Foxtel Digital.

Dave.

Reply to
David L. Jones

To play your dvd collection with decent quality on your HD Plasma, you will now need to buy an Upscaling dvd player like this one.

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Reply to
Just some dude

The following is simplified:

A very simple answer is that you need an HDTV DVD player with the proper cabling, that is compatible to the native resolution of your TV. You then must play program material on the player that is in the HDTV format at the native standard for your TV set.

Watching HDTV programs from a satellite receiver or from a cable service has many variables. The main one is the amount of compression that they use. The higher the compression, the less sharp the images will be. TV distribution services use as much compression as possible to save space. When watching on a small to medium size screen, the image will look a lot sharper than on a very large screen.

For details and requirements for what you want, it is best to see the dealer where you bought the set. They will explain what you must do to have the optimum.

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JANA
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"Zach"  wrote in message 
news:468c1d90$1@dnews.tpgi.com.au...
I recently bought a Panasonic 42 inch HD Plasma.
When I saw it at Hardly Normals, they run this demo through it.
HD Tv some really nice scenery shots from all over the world, Sand Dunes,
beaches ect ect, its a standard demo that most shops use.
Its crystal clear, very sharp image.
But with my Plasma, DVDs are not a sharp, no where near it, why ?
Cheers, Zach
Reply to
JANA

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