Re: Will F1 be on BBC HD?

Bigbird wrote:
Phil Newnham wrote:

Bigbird wrote:
Phil Newnham wrote:

Bigbird wrote:
Ian Rawlings wrote:

On 2009-02-27, Bigbird <bigbird.usenetNOSPAM@xxxxxxxxx> wrote:

Reading it is easy enough interpreting it's relevance is
less so. You failed to assert whether that the transmitted
source was a different ratio.
Big words, little brain.
Ah, I thought as much.

You are unable to answer the simple question without which it is
impossible to evaluate the relevance of your other assertions.
Perhaps you have been holed below the waterline.
Your questions have already been answered, but you didn't
understand what you were being told. The most important one you
missed is that a PAL signal is not digital *at all* - it is
analogue, and if you buy an LCD telly you're relying on good
quality ADC to get good picture.
Perhaps it got lost in all the irrelevant stuff. I skimmed what Ian
wrote and most of it had absolutely no relevance to the foregoing
thread. He appeared fixated on pixel ratio and resolution.
Because pixel ratio and resolution is the key that explains why HD is
better even for SD pictures. I'll try one more time in case you still
have a chance to get it. An SD picture, delivered as PAL, comes as an
analogue signal, split into horizontal lines. The vertical lines are
created by the TV, and on an LCD screen, that means using square
pixels. On an SD screen, there are approximately the "right" number
of pixels for the source signal, on an HD screen there are lots more.
The problem is that a PAL "pixel" doesn't line up exactly to the
square ones on the SD screen, which means that they are all
interpolated, either a little bit or a lot. Most SD screens are
pretty good at doing this. The HD screen also has to interpolate, but
it has more pixels, so it is more capable of making the analogue
picture look right. The early cheap HD screens were poor at doing
this because it is more complex than with SD, and, well, they were
early machines and they were cheap.

Your analogy with the chess board is wrong because the analogue
source does not ever fit to the digital screen.

Is my CRT a digital screen?

Not exactly, but the point you came into the conversation was this:

"> An HD display
> displaying an SD signal has more pixels to use to correct the
> inevitable mapping errors that you get even when using an SD display
> to display an SD signal.
>

Try this. Upscale an 8 pixel by 8 pixel chessboard to 12 pixels by 12
pixels. What size squares do *you* have?"

Now if you thought you were responding to a comment about CRTs vs. LCDs then you were really, really wrong. You're also wrong if you think that a good quality HD LCD displaying a good quality HD picture from a good source is worse than a good quality CRT displaying a good quality SD source, because it isn't. The LCD is much better.

Why do so many standard TV pictures look so much better on my old CRT
that on so many HD TVs. You seem to be trying say they don't, but this
is where my eyes versus your insistence otherwise clearly diverge.

It is where I gave up on Ian also. The OP claimed the picture on his HD
TV is crap, who are you to insist otherwise.

No, the OP said the picture quality last year was very poor. Last year there wasn't any HD F1 in the UK.

You should instead
compare to an mp3 - would you rather have an mp3 that was encoded at
64kbps, or 128kbps?

No that is quite wrong and not at all analogous. Perhaps more analogous
might be to compare mono to pseudo stereo.

By way of example if I watched the GP2 on my brothers 50" HD TV it
would only look good at it's native resolution i.e 576p I assume, but
then the AR would be slightly off IIRC. Upscaling it looked crap, even
if I sat further back. More pixels do not, alone, equal better picture
without a source to match. This is the chessboard analogy.

The aspect ratio of the pixels is always "off", because, as has been already explained, they are not square. That means that, on an SD display, the first pixel is off by a little bit, then the next is off by a little bit doubled, then the next by a little bit tripled etc. until eventually the pixels are almost in sync, then start again. The more pixels, the more ability the screen has to interpolate to better match the source. Your brother's TV is obviously not very good at this but that's a problem with the TV, not the technology. In any case, as you admit here, if you had an HD source, you would get a much better picture.

What I always found funny, and what goes more to the comments about
willy waving made in this thread, is that one of kids might then come
in to watch something and insist that the picture take up the whole
screen regardless of how poor the quality looked or how off theaspect
ratio migh be.

Well, you won't catch me buying a 50" TV, ever, so I won't have that problem I guess.

If you believe that HD telly is rubbish just because the ones
you've seen had poor ADC or were set up wrong, then you're a fool.
If you think my response had anything to do with regarding HD TV as
rubbish then you are a fool.

Like Ian you appear to miss the thread that those complaining are
those with HD TVs that cannot get a decent picture.
Then the answer is quite simple - take it back to the shop. And as
usual, you refer to "those complaining" as if you're not really in
the thread - if you are not complaining then what's your point?

That Ian is wrong to insist that all HD TVs inherently display a better
picture at higher resolutions for every signal than, for instance, the
CRT I use. He is wrong, as are you, to insist on what is plainly not
the case.

He hasn't said any such thing, and neither did I. An HD TV has the potential to display a better picture than your CRT, but as always you will only get the quality you're willing to fork out for, and you should always compare like with like, ie. comparing a 50" plasma with your 32" CRT is not fair and never will be.

--
Phil

http://www.flickr.com/photos/tmc1979/
.

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