Panasonic TH42PV500 Hi-def TV

[Roryquo8]

Hello all.

After months of careful thought I finally went down to buy this Hi-Def TV only to be very disappointed with the picture quality.

Hi-def mode - STUNNING to say the least (pic supplied from Jap. Hard drive in Hi-def).
Playing Commercial DVD - impressive picture and sound.
DVD of Wed. burned by myself - Picture was very disappointing with a fuzzyness and blurring in places.
3CCD Panasonic DV100 on DVD-Ram - Disappointing and same fuzzyness and lack of detail.
Picture from built-in Freeview tuner - Also very disappointing especially on moving images.

Am I expecting to much from plasma? All the above play perfectly well (especially the wedding and camera stuff) on a Panasonic 32in CRT (ex. Hi-def.)
I'm now totally bewildered as to which TV to go for now and would welcome any views you may have.

Cheers.
Mike

[Alan Roberts]

Just remember that the panel has more pixels than's needed for SDTV but less than's needed for HDTV. So HD's downconverted for showing, and looks good, but SD's upconverted for showing, and suffers. Also, bear in mind that you should be judging the panel's performance in SDTV from twice the distance that you judge it from in HDTV. Your 32" tele has no such problems, it simply adjusts the scan rates to suit the pictures, although the scanning spot may not always be appropriate.

[Roryquo8]

Thanks Alan.
Point taken. Looks like I've still got some thinking to do.
Would a Hi-def Camera be the answer to getting the maximum quality out of this particular set? After editing in an appropriate software package would the definition be similar to that from the Japanese hard drive?

I've been looking for a reason to upgrade and looks like I may have found it.
Don't tell the wife!!
Thanks.
Mike

[infocus]

So HD's downconverted for showing, and looks good, but SD's upconverted for showing, and suffers.
I'm not sure that's all the story - if it was then it wouldn't explain why commercial DVDs look "impressive", yet Freeview looks "very disappointing especially on moving images" (Roryquo8's words, but also my experiences) - they are, after all, both SD. What I think is being seen are the problems behind the data rates used for Freeview. In the past, the worst of the Freeview artefacts have been "softened" by the display, and indeed, by the smaller sizes of displays in the past. Now, the displays are getting so good, that they're showing up all the imperfections in a transmission system that has not yet even replaced it's predecessor!

I once remember a fellow student trying a pair of reasonable hi-fi speakers with a cheap stereo system. Subjectively, it sounded worse than with it's own much cheaper speakers, and someone made the comment (somewhat unkindly) that the new speakers just enabled all the distortion to be heard clearly. I think a visual equivalent of that is being experienced here. This, and many similar experiences lead me to have a gut feeling that HD may become mainstream far faster than many peolple believe in their wildest dreams.

[Alan Roberts]

Commercial DVDs, at least the good ones, are MPEG2 encoded using a 2-pass coder to maximise the quality by using variable bit-rate. Also, the coders use very fancy motion detection to drive the coder in the most efficient way. It takes time and care, and a considerable degree of hand-crafting. And the bit-rate can be up to 9Mb/s. Also, most of the spectacularly good DVDs are cinema films, usually widescreen and letter-boxed, even in 16:9, so they aren't full sized pictures, and that means more of the bit-rate goes on what you see (since the black part needs sod all).

Freeview uses hardware encoding, either constant bit-rate of between 2 and 4.5Mb/s depending on the channel, or variable at an average of about 3.2Mb/s. Surprise, surprise, it doesn't look as good.

But apart from all that, the analogue circuitry in most plasma panels is pretty abysmal (e.g. using just one filter to separate chroma from luma, for PAL, NTSC or SECAM). I've peered inside quite a few and never cease to be unimpressed at the quality of design. I've even seen a panel with digital inputs, that decoded it to analogue, then back to the digital bit-stream that the panel actuaqlly needs.

The more expensive panels are more expensive because they're better. Buy a cherap one and the pictures will not be as good. You get what you pay for.

[infocus]

I fully agree with all of that, though suspect in Roryquo8s case the problems he sees are due less to analogue circuitry and filtration than bit rate and coding - otherwise the commercial DVD would have suffered as well? Where I've heard manufacturers are now skimping is in the PAL/NTSC decoders, for the simple reason that anyone who buys such a display is likely to be inputting in some non-composite form, Y/C at the very least. An argument I can see the logic for.

For many people on these boards I think the relevance of these observations may be that reassessments may have to be made of acceptable bit rates for coding to DVD, and consequently the amount of material that can be put onto a DVD. If there is any likelihood of work being shown on such a display, it means that relying on quality assessments on a small tv is now just not good enough. And with the explosion of such TVs in the shops, and the near certainty that they will get bigger, better and cheaper, it becomes more and more likely that ones work WILL get shown on such a display.

As far as the broadcast industry goes, and as I've said before, I strongly believe they are going to have a massive and escalating problem unless they react quickly to the situation. Up until recently, I thought the best that could be hoped for was a "BBC HD" subscription channel on satellite, but am beginning to suspect that at least the mainstream channels (BBC1, BBC2, ITV) will have to switch much sooner than anyone here even dreamed of even a year ago. Yes, there's a problem of "how", but I feel that the subject is now taking on such an importance that a way will just have to be found. In a few months time, I cannot see especially the BBC accepting a situation where retailers proudly demo their wares with offerings off Blu-Ray, Sky, even video game consoles, whilst apologising for the quality on BBC1 as being "very disappointing especially on moving images". I've certainly found the same as Roryquo8, and know we're not alone.

[Alan Roberts]

100% agree with all that. You shouldn't think that lots of other people aren't thinking exactly the same way, progress is happening much faster than was expected even a year ago. The constraints on broadcasters are now ways, means, and money, not will or intent. Many of us in this game have been saying all of this for 15 years or more, now our predictions are coming true.