Digital standards question.
 

Hello.

My flaky understanding of these matters tells me that in t'olden days,
the frame rate of a CRT telly was linked to the frequency of the mains
electricity supply, hence we (UK) had 50Hz / 50 fields/s whilst the
North Americans had 60Hz / 60 fields/s. There would be certain
difficulties in converting shows from one territory to the other due
to this mismatch.

Now that we have the marvellous and beyond reproach digital systems,
do the same restrictions apply? Would a digital system be able to
transmit, receive & display a 60 fields/s show over here & vice versa?

T.I.A.

Digital standards question.
 

On 1 Dec, 15:33, David Paste wrote:
Hello.

My flaky understanding of these matters tells me that in t'olden days,
the frame rate of a CRT telly was linked to the frequency of the mains
electricity supply, hence we (UK) had 50Hz / 50 fields/s whilst the
North Americans had 60Hz / 60 fields/s. There would be certain
difficulties in converting shows from one territory to the other due
to this mismatch.

Now that we have the marvellous and beyond reproach digital systems,
do the same restrictions apply? Would a digital system be able to
transmit, receive & display a 60 fields/s show over here & vice versa?

The electricity supply ceased to matter for display once power
supplies were good enough to prevent mains "hum bars" being visible on-
screen. PC CRT displays happily ran at 60Hz+ in the UK just like the
rest of the world.

Filming under certain lighting can cause problems if the frame rate
doesn't match the flicker rate of the lights.


We have a 50Hz standard in the UK, and we've chosen to stick with it,
even for HD. You could transmit 60Hz if you wanted, and all HD-ready
sets could display it. Most bog standard CRTs can to 60Hz just fine
with a suitable connection (e.g. RGB SCART) - decoding a "foreign"
colour standard from the composite connection is something few do.

Cheers,
David.

Digital standards question.
 

On Tue, 1 Dec 2009 08:20:09 -0800 (PST)
" wrote:
We have a 50Hz standard in the UK, and we've chosen to stick with it,
even for HD. You could transmit 60Hz if you wanted, and all HD-ready
sets could display it. Most bog standard CRTs can to 60Hz just fine
with a suitable connection (e.g. RGB SCART) - decoding a "foreign"
colour standard from the composite connection is something few do.

It used to make me laugh when games reviewers went through a stage back in
the 90s of tossing off over game frame rates and almost passing out when
games went over the magic 100fps mark. Except of course most monitors
of the day could barely make it to an 80hz refresh rate. A point which
apparently was entirely lost on them and the muppets who used to claim they
could really spot the difference between Blood n Guts 2 and Blood n More
Guts 3 on their cheapo 100 quid philips CRT.

B2003

Digital standards question.
 

wrote:
On 1 Dec, 15:33, David Paste wrote:
Hello.

My flaky understanding of these matters tells me that in t'olden days,
the frame rate of a CRT telly was linked to the frequency of the mains
electricity supply, hence we (UK) had 50Hz / 50 fields/s whilst the
North Americans had 60Hz / 60 fields/s. There would be certain
difficulties in converting shows from one territory to the other due
to this mismatch.

Now that we have the marvellous and beyond reproach digital systems,
do the same restrictions apply? Would a digital system be able to
transmit, receive & display a 60 fields/s show over here & vice versa?

The electricity supply ceased to matter for display once power
supplies were good enough to prevent mains "hum bars" being visible on-
screen. PC CRT displays happily ran at 60Hz+ in the UK just like the
rest of the world.

Filming under certain lighting can cause problems if the frame rate
doesn't match the flicker rate of the lights.


We have a 50Hz standard in the UK, and we've chosen to stick with it,
even for HD. You could transmit 60Hz if you wanted, and all HD-ready
sets could display it. Most bog standard CRTs can to 60Hz just fine
with a suitable connection (e.g. RGB SCART) - decoding a "foreign"
colour standard from the composite connection is something few do.

Cheers,
David.

Actually most of the world uses 50 hertz mains, not the other way round.

http://en.wikipedia.org/wiki/List_of...nd_frequencies

Digital standards question.
 

In article 1f3ed13f-7dd2-4176-ad95-
,
wrote:
The electricity supply ceased to matter for display once power
supplies were good enough to prevent mains "hum bars" being visible on-
screen. PC CRT displays happily ran at 60Hz+ in the UK just like the
rest of the world.

Also, it ceased to be practical to use it as a frequency reference with
the start of colour television, as all coding methods relied on signals
with greater stabilities than the mains frequency could ever achieve.

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

Digital standards question.
 

David Paste wrote:
Hello.

My flaky understanding of these matters tells me that in t'olden days,
the frame rate of a CRT telly was linked to the frequency of the mains
electricity supply, hence we (UK) had 50Hz / 50 fields/s whilst the
North Americans had 60Hz / 60 fields/s. There would be certain
difficulties in converting shows from one territory to the other due
to this mismatch.

Now that we have the marvellous and beyond reproach digital systems,
do the same restrictions apply? Would a digital system be able to
transmit, receive & display a 60 fields/s show over here & vice versa?

T.I.A.

Most digital equipment can handle cross conversion relatively easily,
but the source is still different and you may notice some artifacts
especially during movement. For instance Region 1 DVDs are encoded for
60Hz (or NTSC, not that the colour encoding is atall relevent), and
region 2 DVDs are encoded for 50Hz (Pal). However if you have a hacked
player that can play all regions, it will provide the correct output for
your TV, it is hard to see any difference between the 2.

In the old days one would have bought a standards converter from
Lectropacks or such like for about £100 to convert 60Hz VCR output etc,
but with digital displays they all have that kind of
scaler/de-interlacer/frame driver built in anyway because the display
panels tend to be standard and don't match any TV region. Scalers are
horrible things and the main reason why LCD is not as good as CRT, if
you can bypass the scaler you get the best results, hence HDTV source
looks the best on a matched HDTV (not just because it has more pixels).

I think you may still be able to buy a scaler for £3,000 that makes
normal SDTV look like HDTV, it is just a better quality scaler. But TVs
are getting better now with 200Hz equating to an excellent scaler,
simply because it has more processing power, like the £3000 one.

--
Tony