HDTV in the UK
 

Mike Henry wrote:
In , Mike Edwards
wrote:

Annoyingly some will take a 1920 x 1080i signal and overscan it a few
percent - even thought the panel is 1920 x 1080... Sony Bravias do this and
it destroys any fine text in the picture.

[...]
Why not just try one of the new Sony 1080p sets?

Well (not that I'm about to buy an LCD TV of any kind), after reading
the above I'm certainly not buying a Sony TV unless I have a guarantee
that it doesn't overscan in any mode.

AIUI, though I've not seen it for myself yet, the new Bravias have two
modes. One is indeed a 3% overscan, the other is a 'perfect' match. I've got
a feeling the factory ship mode is the former.


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

HDTV in the UK
 

Annoyingly some will take a 1920 x 1080i signal and overscan it a few
percent - even thought the panel is 1920 x 1080... Sony Bravias do this
and
it destroys any fine text in the picture.

[...]
Why not just try one of the new Sony 1080p sets?

Well (not that I'm about to buy an LCD TV of any kind), after reading
the above I'm certainly not buying a Sony TV unless I have a guarantee
that it doesn't overscan in any mode.

AIUI, though I've not seen it for myself yet, the new Bravias have two
modes. One is indeed a 3% overscan, the other is a 'perfect' match. I've got
a feeling the factory ship mode is the former.

Why would they do that? What is the supposed benefit of the overscan
option?

HDTV in the UK
 

In message , Mike
Edwards writes

Annoyingly some will take a 1920 x 1080i signal and overscan it a few
percent - even thought the panel is 1920 x 1080... Sony Bravias do this
and
it destroys any fine text in the picture.

[...]
Why not just try one of the new Sony 1080p sets?

Well (not that I'm about to buy an LCD TV of any kind), after reading
the above I'm certainly not buying a Sony TV unless I have a guarantee
that it doesn't overscan in any mode.

AIUI, though I've not seen it for myself yet, the new Bravias have two
modes. One is indeed a 3% overscan, the other is a 'perfect' match. I've got
a feeling the factory ship mode is the former.

Why would they do that? What is the supposed benefit of the overscan
option?

I would imagine it's to remove all the crud from around the edge of the
picture that you aren't supposed to see... although i don't know why
they don't just use a black border to avoid spoiling the 1:1 pixel
relationship.
--
Chris

HDTV in the UK
 

On Sun, 10 Dec 2006 23:47:08 GMT, Chris
wrote:

AIUI, though I've not seen it for myself yet, the new Bravias have two
modes. One is indeed a 3% overscan, the other is a 'perfect' match. I've got
a feeling the factory ship mode is the former.

Why would they do that? What is the supposed benefit of the overscan
option?

I would imagine it's to remove all the crud from around the edge of the
picture that you aren't supposed to see... although i don't know why
they don't just use a black border to avoid spoiling the 1:1 pixel
relationship.

What "crud" should there be if the lines we are talking about are
specified as active picture lines containing only picture information?
There is already a no-go area of a video signal that is not intended
to be displayed, and which the design and construction of a display
device can be arranged not to display; it's called "blanking".

Rod.

HDTV in the UK
 

Roderick Stewart wrote:

What "crud" should there be if the lines we are talking about are
specified as active picture lines containing only picture information?
There is already a no-go area of a video signal that is not intended
to be displayed, and which the design and construction of a display
device can be arranged not to display; it's called "blanking".

Indeed, though it's not unusual to see VITC that's 'slipped' down into
active picture owing to poor set up of TBCs etc in an edit suite, and DVEs
that still leave the 'other' input channel visible at the picture edges.

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

HDTV in the UK
 

Mark Carver wrote:

Roderick Stewart wrote:

What "crud" should there be if the lines we are talking about are
specified as active picture lines containing only picture information?
There is already a no-go area of a video signal that is not intended
to be displayed, and which the design and construction of a display
device can be arranged not to display; it's called "blanking".

Indeed, though it's not unusual to see VITC that's 'slipped' down into
active picture owing to poor set up of TBCs etc in an edit suite, and DVEs
that still leave the 'other' input channel visible at the picture edges.

Grumble grumble... Over to Wikipedia, then. Let's see...

Vertical Interval TimeCode (VITC, pronounced "vitsee" or sometimes
"vits") is a form of SMPTE timecode embedded as a pair of
black-and-white bars in a video signal. These lines are typically
inserted into the vertical blanking interval of the video signal.

Lots of acronyms for "TBC"... "Time Base Corrector" looks likely...

Timebase correction is a technique to reduce or eliminate errors present
in all analog recordings on mechanical media, including video tape
recorders and videocassette recorders, caused by mechanical instability.
No entry entitled DVE... Try searching on "DVE" and "video"... The entry
on "Vision Mixer" contains those terms...

A vision mixer (also called video switcher, video mixer or production
switcher) is a device used to select between several different video
sources and in some cases composite (mix) video sources together and add
special effects. [...]
Modern vision mixers may also have additional functions, such as machine
control, aux channels for routing signals to other sources than the
program out, macro programming and DVE (Digital Video Effects)
capabilities.

Did I get it right?

--
Dave Farrance

HDTV in the UK
 

Dave Farrance wrote:
Mark Carver wrote:

Indeed, though it's not unusual to see VITC that's 'slipped' down into
active picture owing to poor set up of TBCs etc in an edit suite, and DVEs
that still leave the 'other' input channel visible at the picture edges.

Grumble grumble... Over to Wikipedia, then. Let's see...

Vertical Interval TimeCode (VITC, pronounced "vitsee" or sometimes
"vits") is a form of SMPTE timecode embedded as a pair of
black-and-white bars in a video signal. These lines are typically
inserted into the vertical blanking interval of the video signal.

Lots of acronyms for "TBC"... "Time Base Corrector" looks likely...

Timebase correction is a technique to reduce or eliminate errors present
in all analog recordings on mechanical media, including video tape
recorders and videocassette recorders, caused by mechanical instability.
No entry entitled DVE... Try searching on "DVE" and "video"... The entry
on "Vision Mixer" contains those terms...

A vision mixer (also called video switcher, video mixer or production
switcher) is a device used to select between several different video
sources and in some cases composite (mix) video sources together and add
special effects. [...]
Modern vision mixers may also have additional functions, such as machine
control, aux channels for routing signals to other sources than the
program out, macro programming and DVE (Digital Video Effects)
capabilities.

Did I get it right?

Very good Dave, yes well deduced ! Sorry, I forgot and thought I was
in uk.tech.broadcast, I went a bit OTT with the acronyms :-)

HDTV in the UK
 

In article ,
Dave Farrance wrote:

Vertical Interval TimeCode (VITC, pronounced "vitsee" or sometimes
"vits")

Did I get it right?

I suspect that 'vits' actually stems from "Vertical Interval Test Signal"
which is put on analogue signals leaving the master control on their way to
the transmitter. They are/were used for checking performance of circuits
and transmitters.

--
From KT24 - in "Leafy Surrey"

Using a RISC OS computer running v5.11

HDTV in the UK
 

John Russell wrote:
"aa" wrote in message
. uk...
Item updated today..

http://www.reghardware.co.uk/2006/12...guide_updated/

If it has been updated it does sound a little outdated. This years HD sets
have much better SD scalers and when properly set up make good SD DVB
broadcasts look fantastic. The problem is they also make bad DVB virtually
unwatchable.

I think anyone looking for a large screen (32) would be mad to go out and
get a humungous SD CRT. Your are better off getting a HD Ready LCD/Plasmsa,
even for SD.

The good thing is that bad SD looks so bad the wife will watch Strictly come
Dancing on the CRT in the bedroom, leaving you to watch the HD soccer in
peace.

So "good SD DVB broadcasts look fantastic" but BBC1 at nearly 5Mbps
counts as "bad SD"?!

Where are you finding "good SD DVB" broadcasts?

I realise Strictly Come Dancing is a challenge to MPEG coding, and
frequently pixellates, but so do a lot of things. The majority of DTT
and DSat channels are at lower bitrates, and most aren't even at
720x576, so I doubt these count as "good SD DVB" either.

Just trying to figure uot if what you're saying is that SD looks OK as
long as there are no artefacts, which (IMO) means a progressive image
with little movement and not too much detail. What a useful TV to have!

Cheers,
David.

HDTV in the UK
 

On Mon, 11 Dec 2006 07:43:45 +0000, Roderick Stewart
wrote:

What "crud" should there be if the lines we are talking about are
specified as active picture lines containing only picture information?

The crap that lazy broadcasters can't be bothered to do anything about.
It's amazing how often the phrase "that's in cutoff" or similar gets
mentioned at work. I usually tell them there is no such thing (especially
at the top/bottom on the 14x9 masked stuff we produce) but they usually
give me that look that says "I don't know what you're on about so I'll just
ignore it and carry on anyway".

There is already a no-go area of a video signal that is not intended
to be displayed, and which the design and construction of a display
device can be arranged not to display; it's called "blanking".

Quite. Overscan is a 60 year old anachronism and it should have been binned
long ago. It certainly has no place in modern digital tellies.