Ireland

Mike wrote:
On Thu, 31 May 2007 20:13:16 +0100, Ian Jackson
wrote:

Anyway, I still defy anyone to distinguish (on a normal domestic TV
set) between PAL I, PAL B/G and SECAM. And even NTSC isn't always
that obvious, apart from not flickering as badly as the others three.

Even David Blunkett with his dog fully blindfolded could tell the
difference between NTSC and PAL.

You don't half talk some ********!

On Fri, 01 Jun 2007 23:41:50 +0100, Mike wrote:

Anyway, I still defy anyone to distinguish (on a normal domestic TV set)
between PAL I, PAL B/G and SECAM. And even NTSC isn't always that
obvious, apart from not flickering as badly as the others three.

Even David Blunkett with his dog fully blindfolded could tell the
difference between NTSC and PAL.

I've seen both systems in use at trade exhibitions such as IBC, where
pictures from cameras working on different systems but pointing at the
same test subject are displayed on identical monitors side by side,
and they look pretty much indistinguishable. In the real world, other
factors may give rise to noticeable differences, but I suspect these
are not much to do with the scanning and encoding systems themselves.

Rod.

In message , Roderick
Stewart writes
On Fri, 01 Jun 2007 23:41:50 +0100, Mike wrote:

Anyway, I still defy anyone to distinguish (on a normal domestic TV set)
between PAL I, PAL B/G and SECAM. And even NTSC isn't always that
obvious, apart from not flickering as badly as the others three.

Even David Blunkett with his dog fully blindfolded could tell the
difference between NTSC and PAL.

I've seen both systems in use at trade exhibitions such as IBC, where
pictures from cameras working on different systems but pointing at the
same test subject are displayed on identical monitors side by side,
and they look pretty much indistinguishable. In the real world, other
factors may give rise to noticeable differences, but I suspect these
are not much to do with the scanning and encoding systems themselves.

Rod.

When you play an NTSC DVD on a multi-standard player, and watch it on a
PAL TV set, what are we looking at? Is the picture quality noticeably
worse than when playing a PAL DVD?
Ian.
--

Why did the UK opt for a 6 MHz audio subcarrier, while most of the rest
of Europe went for 5.5 MHz.
Was it an attempt to reduce imported TV sets ?

No, it was to improve the definition. Eastern Europe went even further
with a 6.5MHz audio carrier, allowing equal horizontal and vertical
definition.

Thank you for some illuminating replies - this does also beg the
question as to why the OIRT countries adopted Systems D and K with 6.5
Mhz sound separation and why did the BBC not adopt this instead of PAL
I to further enhance vertical resolution.

In article . com,
AnnieslandJohn wrote:
Why did the UK opt for a 6 MHz audio subcarrier, while most of the rest
of Europe went for 5.5 MHz.
Was it an attempt to reduce imported TV sets ?

No, it was to improve the definition. Eastern Europe went even further
with a 6.5MHz audio carrier, allowing equal horizontal and vertical
definition.

Thank you for some illuminating replies - this does also beg the
question as to why the OIRT countries adopted Systems D and K with 6.5
Mhz sound separation and why did the BBC not adopt this instead of PAL
I to further enhance vertical resolution.

Because the GPO, who were in charge of such matters, went for 8MHz wide
channels for Western European compatibility. I suspect that the co-channel
interference, experienced from continental transmitters (French, Belgian,
Dutch) would look far worse if the vision carriers were not on the same
nominal frequency. And of course, there'd be less channels available for
use if they were wider.

--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

In message , charles
writes
In article . com,
AnnieslandJohn wrote:
Why did the UK opt for a 6 MHz audio subcarrier, while most of the rest
of Europe went for 5.5 MHz.
Was it an attempt to reduce imported TV sets ?

No, it was to improve the definition. Eastern Europe went even further
with a 6.5MHz audio carrier, allowing equal horizontal and vertical
definition.

Thank you for some illuminating replies - this does also beg the
question as to why the OIRT countries adopted Systems D and K with 6.5
Mhz sound separation and why did the BBC not adopt this instead of PAL
I to further enhance vertical resolution.

Because the GPO, who were in charge of such matters, went for 8MHz wide
channels for Western European compatibility. I suspect that the co-channel
interference, experienced from continental transmitters (French, Belgian,
Dutch) would look far worse if the vision carriers were not on the same
nominal frequency. And of course, there'd be less channels available for
use if they were wider.


I'm not sure that it was much to do with transmitter frequencies. In
Europe and Russia (in fact, for most of the world), everybody uses the
same nominal UHF vision frequencies for 625-line TV (+/- the various
offsets). However, at VHF, it's a real hotch-potch (see link).

http://www.pembers.freeserve.co.uk/W...mission-System
s.html#Bands

(Excellent bedtime reading!)

It's more likely that the USSR and the Eastern Block countries adopted
something incompatible with Western Europe in an attempt to stop their
population from being able to watch 'free world' TV (or at least make it
difficult). And I suspect that France had a hand in convincing them of
the superiority of SECAM. Sensibly, they didn't use SECAM-L, with its
positive vision modulation and AM sound (shades of UK 405-line TV).
However, a SECAM-D/K set does get a B&W picture when watching PAL B/G or
I (but no sound, of course).

Ian.
--

In article ,
Ian Jackson wrote:

It's more likely that the USSR and the Eastern Block countries adopted
something incompatible with Western Europe in an attempt to stop their
population from being able to watch 'free world' TV (or at least make it
difficult). And I suspect that France had a hand in convincing them of
the superiority of SECAM.

France certainly convinced the USSR to use SECAM. I suspect that at the
time, memories were long and a German system (PAL) was not wanted and at
the time an American one wasn't acceptable either. Once the USSR adopted
SECAM, the rest of the Warsaw Pact countries fell into line.



Sensibly, they didn't use SECAM-L, with its positive vision modulation
and AM sound (shades of UK 405-line TV).

and 819.

But remember there already was a monochrome system operating east of the
Iron Curtain - SECAM was simply added to that system




--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

On Sat, 2 Jun 2007 13:21:25 +0100, Ian Jackson
wrote:

I've seen both systems in use at trade exhibitions such as IBC, where
pictures from cameras working on different systems but pointing at the
same test subject are displayed on identical monitors side by side,
and they look pretty much indistinguishable. In the real world, other
factors may give rise to noticeable differences, but I suspect these
are not much to do with the scanning and encoding systems themselves.

Rod.

When you play an NTSC DVD on a multi-standard player, and watch it on a
PAL TV set, what are we looking at? Is the picture quality noticeably
worse than when playing a PAL DVD?

It depends.

It depends on whether you're really looking at NTSC (or the
*******ised form of it with the wrong subcarrier that they use on
domestic PAL equipment), or RGB.

It depends on whether you have your DVD player set to produce an
output signal with the same line standard as on the disk, or to
convert everything to PAL 625/50 as some of them can do, with varying
degrees of success.

Best case, native format RGB.
Worst case, DVD converts to "PAL", and you actually use the composite
PAL output.

Another factor to consider is that most commercial DVDs are not video
sourced but made from cinema films originally shot at 24fps, so there
will be conversion artefacts that wouldn't be present for pure video,
and they will be different for the two video systems. In other words,
a commercial DVD movie is not a fair test of the video systems.

I still maintain that actual NTSC and PAL video signals straight from
cameras to studio monitors are practically indistinguishable, and
generally superb compared with anything I've ever seen at home.

Rod.

On Sat, 02 Jun 2007 13:00:36 +0100, Roderick Stewart
wrote:

On Fri, 01 Jun 2007 23:41:50 +0100, Mike wrote:

Anyway, I still defy anyone to distinguish (on a normal domestic TV set)
between PAL I, PAL B/G and SECAM. And even NTSC isn't always that
obvious, apart from not flickering as badly as the others three.

Even David Blunkett with his dog fully blindfolded could tell the
difference between NTSC and PAL.

I've seen both systems in use at trade exhibitions such as IBC, where
pictures from cameras working on different systems but pointing at the
same test subject are displayed on identical monitors side by side,
and they look pretty much indistinguishable. In the real world, other
factors may give rise to noticeable differences, but I suspect these
are not much to do with the scanning and encoding systems themselves.

Trade exhibitions are hardly the real world. In the real world where
the tv signal travels through the atmosphere NTSC, in its analogue
form, is noticeably worse on just about every measure.


--

On Tue, 05 Jun 2007 10:35:35 +0100, Mike wrote:

I've seen both systems in use at trade exhibitions such as IBC, where
pictures from cameras working on different systems but pointing at the
same test subject are displayed on identical monitors side by side,
and they look pretty much indistinguishable. In the real world, other
factors may give rise to noticeable differences, but I suspect these
are not much to do with the scanning and encoding systems themselves.

Trade exhibitions are hardly the real world. In the real world where
the tv signal travels through the atmosphere NTSC, in its analogue
form, is noticeably worse on just about every measure.

This is true, but I think seeing the two systems side by side with
nothing more than cameras and monitors involved is a good way of
isolating them from other effects and making a fair comparison of
intrinsic system properties. If you try to compare analogue television
scanning and encoding standards by comparing playback signals derived
from bit-rate-reduced digital video of cine film scanned at unknown
rates and possibly also standards-converted as well as encoded in a
piece of domestic equipment, you can't be really sure what you're
comparing at all.

DVD, particularly DVD of film, is not broadcast quality and therefore
not valid source material for comparing broadcast systems.

Rod.