psychological problem
 

Today I has a customer who expressed dissatisfaction with the picture on his
Panasonic plasma. He clicked through the analogue channels, then switched to
Sky HD (via the HDMI) and flicked through the SD channels. "None of them are
good pictures!" When I put an HD channel on he said "That's a lot better."
It wasn't that he didn't understand the difference between HD and SD. In
concept he did. But he'd got used to Sky HD and the HD picture from the
games machine, and it was making him think that there was something wrong
with an SD picture.
This is to me an interesting new development, which I suppose could have
been predicted.

Bill

psychological problem
 

Bill Wright wrote:
Today I has a customer who expressed dissatisfaction with the picture on his
Panasonic plasma. He clicked through the analogue channels, then switched to
Sky HD (via the HDMI) and flicked through the SD channels. "None of them are
good pictures!" When I put an HD channel on he said "That's a lot better."
It wasn't that he didn't understand the difference between HD and SD. In
concept he did. But he'd got used to Sky HD and the HD picture from the
games machine, and it was making him think that there was something wrong
with an SD picture.
This is to me an interesting new development, which I suppose could have
been predicted.

Bill


Actually you're right on this, because when I watch BBC hD from my
MythTV box and go back to SD it's hideous to watch. Maybe that's an
exaggeration but it's not far from the truth.

Rob.

psychological problem
 

In article ,
Robert Wilson wrote:
Actually you're right on this, because when I watch BBC hD from my
MythTV box and go back to SD it's hideous to watch. Maybe that's an
exaggeration but it'

Strange. I find a great deal of BBC HD hardly any different from SD. Less
movement artifacts - but hardly 'high definition'. Bonekickers tonight a
prime example of this.

Wimbledon looked stunning where HD cameras were in use, though.

--
*Why isn't 11 pronounced onety one? *

Dave Plowman London SW
To e-mail, change noise into sound.

psychological problem
 

Mike Henry wrote:
Obviously the quality of the scaling wizzardy in his TV will have a large
effect on how good it looks - but something else has occurred to me. If
there are going to be lots of people upset with the quality of SD
broadcasts, perhaps it will increase pressure on the broadcasters to
increase SD bitrates so we will all benefit. You never know.

I wonder how many people watch the 95% of C4-HD that is nothing more than
C4-SD upconverted and broadcast at 15Mb/s:MPEG4, and think all of what they
see on there is HD ?


--
Mark
Please replace invalid and invalid with gmx and net to reply.

psychological problem
 

So what exactly was he moaning about in the picture? Way back in the 70s, I
used to watch the 819 line French black and white signals and when you
flipped to bbc 2 colour, the definition was definitely worse.

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
__________________________________________________ __________________________________________________ __________


"Bill Wright" wrote in message
...
Today I has a customer who expressed dissatisfaction with the picture on
his Panasonic plasma. He clicked through the analogue channels, then
switched to Sky HD (via the HDMI) and flicked through the SD channels.
"None of them are good pictures!" When I put an HD channel on he said
"That's a lot better."
It wasn't that he didn't understand the difference between HD and SD. In
concept he did. But he'd got used to Sky HD and the HD picture from the
games machine, and it was making him think that there was something wrong
with an SD picture.
This is to me an interesting new development, which I suppose could have
been predicted.

Bill

psychological problem
 

But many view vhs videos still and are quite happy.

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
__________________________________________________ __________________________________________________ __________


"Robert Wilson" wrote in message
et...
Bill Wright wrote:
Today I has a customer who expressed dissatisfaction with the picture on
his Panasonic plasma. He clicked through the analogue channels, then
switched to Sky HD (via the HDMI) and flicked through the SD channels.
"None of them are good pictures!" When I put an HD channel on he said
"That's a lot better."
It wasn't that he didn't understand the difference between HD and SD. In
concept he did. But he'd got used to Sky HD and the HD picture from the
games machine, and it was making him think that there was something wrong
with an SD picture.
This is to me an interesting new development, which I suppose could have
been predicted.

Bill
Actually you're right on this, because when I watch BBC hD from my MythTV
box and go back to SD it's hideous to watch. Maybe that's an exaggeration
but it's not far from the truth.

Rob.

psychological problem
 

Bill Wright wrote:
...But he'd got used to Sky HD and the HD picture from the
games machine, and it was making him think that there was something wrong
with an SD picture.

10 Years ago I worked on the design of HD gear and SD always looked
horrible when I got home. I didn't think I'd still be watching it in 2008.
Arthur

psychological problem
 

"Brian Gaff" wrote in message
om...
So what exactly was he moaning about in the picture?

On Sky SD, mainly the results of compression.

Bill

psychological problem
 

"Arthur" wrote in message
...
Bill Wright wrote:
...But he'd got used to Sky HD and the HD picture from the
games machine, and it was making him think that there was something wrong
with an SD picture.

10 Years ago I worked on the design of HD gear and SD always looked
horrible when I got home. I didn't think I'd still be watching it in 2008.
Arthur

Remind me again, how long after the arrive of 625 was it before 405 was
finally shut down ;-) ? Things will be even "worse" this time because TVs
are more reliable so there's no incentive to "move up because the current
one has broken" for those luddites like me. Besides which, on a 28 inch, I
can't imagine my eyesight would see much difference.

Paul DS.

psychological problem
 

Paul D.Smith wrote:

Remind me again, how long after the arrive of 625 was it before 405 was
finally shut down ;-) ? Things will be even "worse" this time because
TVs are more reliable so there's no incentive to "move up because the
current one has broken" for those luddites like me. Besides which, on a
28 inch, I can't imagine my eyesight would see much difference.

I can certainly spot the difference on 20inch 'professional' CRT and LCD
monitors, though they are being fed with uncompressed 270 Mb/s (SD) or
1.485 Gb/s (HD) signals

I think you would notice the difference on a 26ish inch display, though
what hits you first is the vast reduction of compression artefacts,
rather than spacial resolution at that size.

C4 HD with its upconverted SD programming looks fantastic (at current HD
bit rates and coding), much better than clean analogue reception of the
same broadcast.

psychological problem
 

On Jul 23, 5:40*pm, Mike Henry
wrote:

You say "nothing more" but I think that's underplaying it. It's supposed
to look really good though, I heard? Bearing in mind it's the original
uncompressed SD which is upconverted, not the end-user artefact-ridden
mpeg2 that you'd see if you fed C4 SD to your TV.

What format are the master tapes of C4's SD stuff in though? I bet
they're just highish bitrate MPEG2 with the same inadequate number of
horizontal samples as SD DVB.

Not to mention that it'll be C4's pro gear doing the upscaling, again
better than a domestic TV doing it.

There's still rescaling within the TV, because most flat panels are
1366x768 - so 720p has to be zoomed to fill the screen, and overscan
is added too.
In addition, 1080i has to be deinterlaced, and many flat panels make
an awful job of this.

If non-techy people think that all that content on C4HD is HD, it's a
testament to how poor SD is (post-2000 Olympics bitrates) that there is
such a marked difference surely?

Non-MPEG'd SD (as seen on German satellite but nowhere else) does look
comparable to HD, even when viewed on a flat panel LCD - the panels'
deinterlacing has much less of a negative effect on the picture
quality than MPEG2 compression does, it would seem.

psychological problem
 

psychological problem
 

In article , Mark Carver wrote:
I've been in studio galleries, and OB trucks, and many non technical types
will comment how marvellous the 'HD' pictures are when what they're looking at
is the HD signal downconverted and displayed as SD on an SD monitor.

Same here. Even ordinary bog-standard TV is marvellous coming straight out of
the camera, and even broadcast digital recording can't do too much damage to it,
but it's all downhill from then on. The wretched process of transmitting it to
the viewer seems to be the worst bit. We wouldn't need to bother with high
definition if we only made the best of what we've already got.

That said, taking HD cameras and sources, and making your programme in the
1080i domain, results in a far better picture in SD (even after it's been
through the emission level MPEG coding and been compressed to hell and back)
than doing that production in SD.

Agreed again, and anyone with a digital stills camera has probaly discovered the
same. It must be something to do with the way the high spatial frequencies are
filtered. Shooting with a camera that is only capable of resolving the amount of
detail in the final output is probably equivalent to a brickwall filter, but
shooting at higher resolution allows it to be filtered more smoothly.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

psychological problem
 

On Jul 25, 11:06*pm, Roderick Stewart
wrote:


Agreed again, and anyone with a digital stills camera has probaly discovered the
same. It must be something to do with the way the high spatial frequencies are
filtered. Shooting with a camera that is only capable of resolving the amount of
detail in the final output is probably equivalent to a brickwall filter, but
shooting at higher resolution allows it to be filtered more smoothly.

It's probably because the downconverted image is full of 'jaggies' -
this has the effect of making everything seem sharper (even the
background parts of the image, which would normally be out of focus)
but in reality it's just another form of picture distortion.

psychological problem
 

In article en.co.uk,
Roderick Stewart wrote:
Same here. Even ordinary bog-standard TV is marvellous coming straight
out of the camera, and even broadcast digital recording can't do too
much damage to it, but it's all downhill from then on. The wretched
process of transmitting it to the viewer seems to be the worst bit. We
wouldn't need to bother with high definition if we only made the best
of what we've already got.

In one. Try explaining this to the average punter and you get blank looks,
though.

However I'd take issue about everything being marvellous straight out of
the camera too. Straight out of a good camera using a good lens with
someone who knows how to rack the channel, more like.

--
*I finally got my head together, now my body is falling apart.

Dave Plowman London SW
To e-mail, change noise into sound.

psychological problem
 

In article , Dave Plowman (News) wrote:
However I'd take issue about everything being marvellous straight out of
the camera too. Straight out of a good camera using a good lens with
someone who knows how to rack the channel, more like.

Of course. I was taking that as assumed. The real eye-opener is that when
you've seen cameras at trade exhibitions where several of them with
different scanning standards are pointing at the same set, matched for
exposure and colour balance, and displayed on monitors which are placed
side by side, and noted that it's usually very difficult indeed to see any
difference between them, you do wonder what all the fuss is about. The
number of lines in the picture seems to be the one thing that makes the
least difference to the perceived quality of the result. Revamping the
entire system and flogging millions of new displays to the public seems
like a pointless expense if you're going to continue shooting rubbish and
feeding it through a data-mangling transmission system.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

psychological problem
 

On 2008-07-26, Roderick Stewart wrote:

Revamping the
entire system and flogging millions of new displays to the public seems
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
like a pointless expense if you're going to continue shooting rubbish and
feeding it through a data-mangling transmission system.

Isn't that the point?

--
David Taylor

psychological problem
 

In article ,
Mike Henry wrote:
In , "Dave Plowman (News)"
wrote:

However I'd take issue about everything being marvellous straight out of
the camera too. Straight out of a good camera using a good lens with
someone who knows how to rack the channel, more like.

As an average punter, I don't know what the term "rack the channel"
means. Please would you explain? Ta!

Adjust the electronics of the camera correctly. There are a vast number of
adjustments on pro cameras.

--
*Seen it all, done it all, can't remember most of it*

Dave Plowman London SW
To e-mail, change noise into sound.

psychological problem
 

"Brian Gaff" wrote in message
m...
But many view vhs videos still and are quite happy.

Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:


When I worked for Granada Rentals, we offered a had a Hitachi
VHS machine, the first model we had offered that was dual speed.
There were components incorporated to deliberately degrade the
SP playback so the LP playback did not look so bad in comparison.
I_kid_you_not.
--
Graham.

%Profound_observation%

psychological problem
 

"Mike Henry" wrote in message
...
In , "Dave Plowman (News)"
wrote:

However I'd take issue about everything being marvellous straight out of
the camera too. Straight out of a good camera using a good lens with
someone who knows how to rack the channel, more like.

As an average punter, I don't know what the term "rack the channel" means.
Please would you explain? Ta!

I'm only an average punter too so no doubt one of the pro's will correct
me as necessary.

The term is historical. Studio cameras used to be two part affairs The
familiar bits was linked by a thick cables to a rack of Camera Control
Units where a "Racks Engineer" made the adjustments using a picture monitor
and much more importantly a waveform monitor and vectorscope.
Well, how did I do?


--
Graham.

%Profound_observation%

psychological problem
 

In article , David Taylor
wrote:
Revamping the
entire system and flogging millions of new displays to the public seems
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
like a pointless expense if you're going to continue shooting rubbish and
feeding it through a data-mangling transmission system.

Isn't that the point?

That depends on who you are. If your job is flogging equipment then I suppose
the point of television is to flog equipment, but if you're a viewer, then the
point of television is programmes, and you just want to be able to see them
properly. Of all the people in the world whose lives are touched by
television, I should think viewers outnumber all the rest by a considerable
margin.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

psychological problem
 

On Jul 23, 12:28*pm, Mark Carver wrote:

I think you would notice the difference on a 26ish inch display, though
what hits you first is the vast reduction of compression artefacts,
rather than spacial resolution at that size.

C4 HD with its upconverted SD programming looks fantastic (at current HD
bit rates and coding), much better than clean analogue reception of the
same broadcast.

Define 'clean analogue reception'.
The analogue pictures from Winter Hill have all the artefacts of an
MPEG2 feed, except for the extreme pixellation which DTH digital
viewers are used to. Movement is not tracked accurately/naturally,
objects blur while they are moving, twitter ('flickering' around sharp
objects) is very noticible and surface textures of objects are not
clearly defined.
Some of this can also be attributed to the aspect ratio conversion to
14:9.

psychological problem
 

Graham wrote:

The term is historical. Studio cameras used to be two part affairs The
familiar bits was linked by a thick cables to a rack of Camera Control
Units where a "Racks Engineer" made the adjustments using a picture monitor
and much more importantly a waveform monitor and vectorscope.
Well, how did I do?

Not bad. Though 'camera channels' as they're called still have the main two
components. The camera head, which contains the image sensors, and has the
lens and viewfinder bolted on, connected by triaxial cable or fibre optic to
the CCU (Camera Control Unit). The CCU lives in the apparatus room, or inside
the OB truck. Then each CCU has an RCP or OCP (Remote/Operational Control
panel). This normally has a joystick to control iris settings, and controls
for white balance, black balance, gamma correction, gain, etc. The cameraman
only has control of pan, tilt, zoom and focus, all other parameters are
controlled by the vision or 'racks' engineer in the control room/OB tech area.
The Europeans call this function 'shading'. Some systems will also have an MSU
(Master Set Up unit) where many of the set up parameters can be globally
applied to more than one camera at once.

Sony RCP :-

http://www.sony.co.uk/biz/view/ShowProduct.action?product=RCP-750&site=biz_en_GB&pageType=Overview&imageType=Mai n&category=ControlSystems

Sony MSU:-

http://www.sony.co.uk/biz/view/ShowProduct.action?product=MSU-900&site=biz_en_GB&pageType=Overview&imageType=Mai n&category=ControlSystems

Sony CCU:-

http://www.sony.co.uk/biz/view/ShowProduct.action?product=HDCU-1500&site=biz_en_GB&pageType=Overview&imageType=Ma in&category=ControlSystems

Sony HD Camera Head:-

http://www.sony.co.uk/biz/view/ShowProduct.action?product=HDC-1500&site=biz_en_GB&pageType=Overview&imageType=Ma in&category=HDseries


(Other manufacturers of broadcast camera equipment are available)




--
Mark
Please replace invalid and invalid with gmx and net to reply.

psychological problem
 

psychological problem
 

On Jul 27, 3:25*pm, Mark Carver wrote:
wrote:
Define 'clean analogue reception'.

A signal from an analogue transmitter fed from a lightly or zero compressed
digital link.
Like Crystal Palace for instance.

What sort of digital link would that be then? Also, how much of is
ARCd 14:9, and how many horizontal samples are there? It's looking
less like clean analogue after all, isn't it :p

The analogue pictures from Winter Hill have all the artefacts of an
MPEG2 feed, except for the extreme pixellation which DTH digital
viewers are used to. Movement is not tracked accurately/naturally,
objects blur while they are moving, twitter ('flickering' around sharp
objects) is very noticible and surface textures of objects are not
clearly defined.

Oh well, Winter Hill analogue will be shutting down for good next year, so
none of that will trouble you :-)

I rarely watch broadcast television in any of its forms and when I do
it's usually German analogue (yes I speak German).

psychological problem
 

psychological problem
 

In article , Mark Carver wrote:
The term is historical. Studio cameras used to be two part affairs The
familiar bits was linked by a thick cables to a rack of Camera Control
Units where a "Racks Engineer" made the adjustments using a picture monitor
and much more importantly a waveform monitor and vectorscope.
Well, how did I do?

Not bad. Though 'camera channels' as they're called still have the main two
components. The camera head, which contains the image sensors, and has the
lens and viewfinder bolted on, connected by triaxial cable or fibre optic to
the CCU (Camera Control Unit).

The "camera head" part used to be just that, incapable of any function on its
own, with only the most vital electronic circuitry that had to be close to the
tubes, the bulk of the circuitry including all the clever video processing being
in the CCU, even the PAL/NTSC encoding being in yet another separate box.

Nowadays a camera head is usually a complete camera including PAL/NTSC and
digital processing and its own sync pulse generator with genlock. Even if it
doesn't include a recording machine as well, it will usually be capable of
providing a fully formed composite or digital video output, working with its
circuits in preset or "auto" mode without any control unit or pulse generator
being connected to it. And it won't need four people to lift it. Times change.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

psychological problem
 

In article 0c074c69-30fd-4abf-8006-
, wrote:
I rarely watch broadcast television in any of its forms and when I do
it's usually German analogue (yes I speak German).

I don't speak German but sometimes watch their transport TV channel on the
internet - "Bahn TV". They have a great programme at 2330 (our time) where
they just clamp a camera on the front of a train and broadcast the entire
journey, usually an hour or so. It's completely mindless, but surprisingly
restful to watch. There is no commentary, no music, no camera moves, no
gimmicks whatsoever, just a brief scrolling caption telling the name of
each station as we approach. No, I'm not a train freak. It's just like
going on a journey and being able to watch the scenery because somebody
else is driving. It must cost only buttons to produce, so I wonder why
nobody else has thought of it.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

psychological problem
 

On Sun, 27 Jul 2008 17:16:20 +0100, Roderick Stewart
wrote:

...
It must cost only buttons to produce, so I wonder why
nobody else has thought of it.

Do you remember the 'Victoria to Brighton' in one minute in the '50s?

--
Alan White
Mozilla Firefox and Forte Agent.
Twenty-eight miles NW of Glasgow, overlooking Lochs Long and Goil in Argyll, Scotland.
Webcam and weather:- http://windycroft.gt-britain.co.uk/weather

psychological problem
 

"Roderick Stewart" wrote in
message .myzen.co.uk...
In article 0c074c69-30fd-4abf-8006-
, wrote:
I rarely watch broadcast television in any of its forms and when I do
it's usually German analogue (yes I speak German).

I don't speak German but sometimes watch their transport TV channel on the
internet - "Bahn TV". They have a great programme at 2330 (our time) where
they just clamp a camera on the front of a train and broadcast the entire
journey, usually an hour or so. It's completely mindless, but surprisingly
restful to watch. There is no commentary, no music, no camera moves, no
gimmicks whatsoever, just a brief scrolling caption telling the name of
each station as we approach. No, I'm not a train freak. It's just like
going on a journey and being able to watch the scenery because somebody
else is driving. It must cost only buttons to produce, so I wonder why
nobody else has thought of it.

3-sat used to do this with a road journey every night after closedown. I've
often thought about recording the output from the cameras on my van, as
evidence when some clot crashes into me.

Bill

psychological problem
 

"Alan White" wrote in message
...
On Sun, 27 Jul 2008 17:16:20 +0100, Roderick Stewart
wrote:

...
It must cost only buttons to produce, so I wonder why
nobody else has thought of it.

Do you remember the 'Victoria to Brighton' in one minute in the '50s?

There's a few on Youtube, including Leeds-London on the M1.

Bill

psychological problem
 

On Jul 27, 5:16*pm, Roderick Stewart
wrote:
In article 0c074c69-30fd-4abf-8006-

, wrote:
I rarely watch broadcast television in any of its forms and when I do
it's usually German analogue (yes I speak German).

I don't speak German but sometimes watch their transport TV channel on the
internet - "Bahn TV". They have a great programme at 2330 (our time) where
they just clamp a camera on the front of a train and broadcast the entire
journey, usually an hour or so. It's completely mindless, but surprisingly
restful to watch. There is no commentary, no music, no camera moves, no
gimmicks whatsoever, just a brief scrolling caption telling the name of
each station as we approach. No, I'm not a train freak. It's just like
going on a journey and being able to watch the scenery because somebody
else is driving. It must cost only buttons to produce, so I wonder why
nobody else has thought of it.

Yes I've seen that :) There's also one on the HR channel called
Hessenbilder, where they just show random towns and cities throughout
mainland Europe - the architecture, and the people going about their
daily lives - and play soothing light trance music.
It's much better than the BBC's offering of "Pages from Ceefax".

psychological problem
 

On Jul 27, 4:09*pm, Mark Carver wrote:
wrote:
On Jul 27, 3:25 pm, Mark Carver wrote:
wrote:
Define 'clean analogue reception'.
A signal from an analogue transmitter fed from a lightly or zero compressed
digital link.
Like Crystal Palace for instance.

What sort of digital link would that be then?

A BT 'Facilityline' circuit, which London is festooned with. 270 Mb/s
uncompressed SDI. Or an Energis (or is it C&W now ?) 140 Mb/s composite link,
to name but two.

Well it's either one or the other, so which one? :p
In any event, the BBC have ARCs within their playout system-
everything's in a 16:9 frame remember - and if, as other people have
suggested, they're moving to a server-based programme source, then
high bitrates for said sources seem less likely.

Admittedly I haven't seen TV from Crystal Palace, but all the UK
analogue transmissions I've seen since 1999 have looked just as bad as
Winter Hill does, with the exception of S4C analogue. I think people
are just used to the low quality, because they have nothing better to
compare it with.

Also, how much of is
ARCd 14:9, and how many horizontal samples are there? It's looking
less like clean analogue after all, isn't it :p

I muck around with ARCs quite often, I've not noticed any artefacts looking at
the output on pro kit, that's not to say there aren't. I'll stick a frequency

ARCing can only be done either by discarding lines or, as with the
'pro' ones, by deinterlacing, rescaling-via-interpolation, then
reinterlacing again. Either way, it will always be lossy.

sweep though one next time I'm playing. I thought it's commonly accepted that
UK analogue transmission, with clean reception, (and a decent input feed to
the Tx) looks subjectively better for most than DVB. Perhaps I'm wrong. I'm no
where near Winter Hill's service area, so I can't comment on that Tx (though
you seem to be the only person on Usenet that has a problem with its analogue
quality ?)

Yes I'd agree it still looks better than direct-to-home DVB, due to
higher bitrates, but worse in some ways.
I hope they increase freeview bitrates after analogue switch-off, but
now that people have bought these PVRs, they probably won't, as it
would shorten recording times :|

psychological problem
 

In article , Bill Wright wrote:
3-sat used to do this with a road journey every night after closedown. I've
often thought about recording the output from the cameras on my van, as
evidence when some clot crashes into me.

I bet there are some people already doing this. Within a few years you'll be
able to buy a standard DIY kit from Halfords, a few years after that it'll be
available as a built-in option on some new cars, then they'll all offer it,
then it'll be a legal requirement for all cars and included in the MOT test,
and next thing after that insurance companies will start turning down claims
unless they're supported by video evidence from them. I'd guess it'll all
happen in less than 10 years.

You mark my words.

Rod.
--
Virtual Access V6.3 free usenet/email software from
http://sourceforge.net/projects/virtual-access/

psychological problem
 

psychological problem
 

On Jul 27, 8:07*pm, Mark Carver wrote:

It may not be either of them, but something else. I doubt you'd see any
difference at home between any of the 34 Mb/s distribution systems

Depends upon which codec is used.



Typical server storage bit rates are 30-50 Mb/s

Compressed using MPEG2?
Stll lower than many digital tapes. They must have some seriously big
hard drive arrays.


Admittedly I haven't seen TV from Crystal Palace, but all the UK
analogue transmissions I've seen since 1999 have looked just as bad as
Winter Hill does, with the exception of S4C analogue.

Well that's very interesting, because since about 1996 S4C has distributed its
signal to its analogue transmitters using early 1990s design Thomson 34 Mb/s
codecs.

I knew they were using an older technology, but I prefer it to MPEG2.
The bilingual service of S4C has no DVB version, and although they may
be using server-based playout for it by now, the last time I checked
it still looked good, at least while Welsh 4:3 programmes were being
shown. :p

ARCing can only be done either by discarding lines or, as with the
'pro' ones, by deinterlacing, rescaling-via-interpolation, then
reinterlacing again. Either way, it will always be lossy.

Yes, but by the time there's PAL code/decode artefacts and filtering added
(remember we're talking about analogue transmission) I doubt you'd notice any
conversion artefacts when using a decent quality ARC (Axon, Snell and Wilcox,
etc).

PAL artefacts and ARCing artefacts each affect the picture in very
different ways.

psychological problem
 

"Roderick Stewart" wrote in
message .myzen.co.uk...
You mark my words.

We always do.

Bill

psychological problem
 

psychological problem
 

On Jul 28, 7:31*am, Mark Carver wrote:

Yes, but remember that archiving is still done on tape based systems [1], the
servers *don't hold the entire programme library, only what is to be broadcast
in the coming days.

That seems odd - because if a programme was repeated at some point in
the future, it'd have to be recopied?
The whole server thing also adds yet another MPEG recode into the
chain, bringing it to at least 3 (at least 4 for people watching the
English sub-regions of BBC1).


[1]
http://www.sony.co.uk/biz/view/ShowProduct.action?product=PetaSite+S2....

Interesting :)


I knew they were using an older technology, but I prefer it to MPEG2.
The bilingual service of S4C has no DVB version, and although they may
be using server-based playout for it by now, the last time I checked
it still looked good, at least while Welsh 4:3 programmes were being
shown. :p

But they are still ARC'd from a 16:9 playout environment.

Well, the lack of a DVB version of the same channel means it doesn't
have to be widescreen equipped. So although they would have to ARC
16:9 material to 14:9, this was/is probably done before it reached the
vision mixers etc. and no further ARCing would be needed.


PAL artefacts and ARCing artefacts each affect the picture in very
different ways.

I don't think I've ever noticed an ARC artefact on analogue TV. Have you got a
screen shot to illustrate your point ? I've not seen in the 10 years I've
occupied these groups a single mention of such an effect (yours excepted)..

What sort of thing are you looking for? In the case of 16:9FHA
converted to 14:9 and 16:9 letterbox, the artefacts would simply be a
loss of sharpness, due to the rescaling process, and an unnatural
tracking of movement, due to the deinterlace-reinterlace process.
Nothing that one can point to in a screenshot.
In the case of 16:9FHA converted to 4:3 centre-cut, no rescaling or
deinterlacing is required, so the above doesn't apply, but the picture
would still be lacking in horizontal samples, assuming the 16:9
programme source was 720x576.


You seemed to have missed my original point. Upconverted C4 SD, via the C4 HD
channel looks better than the same output as seen on analogue.

I was merely pointing out the reasons why it looks better - ie. the
shortcomings of the SD broadcast chains, most of which could be
avoided or improved upon if broadcasters cared.

psychological problem
 

In article o.uk.invalid,
Alan Pemberton wrote:
only has control of pan, tilt, zoom and focus, all other parameters are
controlled by the vision or 'racks' engineer in the control room/OB tech
area.
The Europeans call this function 'shading'.

Do they really? I wonder why? The original BBC iconoscope cameras were
such that they needed constant adjustment. So much so that it was
impossible to cut instantly between them. Camera changes had to be by
means of very slow dissolves, during which the 'racks' operators
adjusted the 'shading' of both the cameras involved.

Yes, "tilt" and "bend" were the adjustments. I think the slow dissolves were
because the engineers only had one monitor and could only see the picture as
it was brought up on air. Surprising that such a simple idea as previewing a
shot before transmitting it wasn't thought of right at the start.

Or maybe it was just to be kind to the primitive sync separators everybody
would be using then, in case the sudden change in signal level on a picture
cut would cause TV sets to lose lock. Or perhaps both.

I would have thought that by the time telly reached the continent this
practice would have been outdated. But terms tend to stick around in
broadcasting circles, even in this competitive, multichannel era...

I'm sure the continent had television before the various orthicon tubes
appeared, so I guess they must have had to tilt and bend as well.

Rod.
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