HomeCinemaBanter

HomeCinemaBanter (http://www.homecinemabanter.com/index.php)
-   UK digital tv (http://www.homecinemabanter.com/forumdisplay.php?f=5)
-   -   psychological problem (http://www.homecinemabanter.com/showthread.php?t=59655)

[email protected] July 25th 08 08:06 PM

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.

Mark Carver July 25th 08 08:22 PM

psychological problem
 
wrote:
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.


DigiBeta, 140ish Mb/s 2:1ish very light compression. Acquisition formats will
often be lower quality however.

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.


I've got the overscan switched off, so the 1080i is preserved from the MPEG4
decoder in the box, into HDMI (uncompressed serial digital interface) and into
the telly.

In addition, 1080i has to be deinterlaced, and many flat panels make
an awful job of this.


Agreed

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.


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.

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.

Although 1080p broadcasting remains the holy grail, there are now moves to
produce all programming in 1080p, because you can downconvert to any 'lesser'
HD or SD format with a minimum loss of quality.


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

Roderick Stewart[_2_] July 26th 08 12:06 AM

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/


[email protected] July 26th 08 12:22 AM

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.

Dave Plowman (News) July 26th 08 10:29 AM

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.

Roderick Stewart[_2_] July 26th 08 12:44 PM

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/


David Taylor July 26th 08 02:49 PM

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

Dave Plowman (News) July 26th 08 04:12 PM

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.

Graham July 26th 08 05:17 PM

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%



Graham July 26th 08 05:46 PM

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%




All times are GMT +1. The time now is 08:16 PM.

Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
HomeCinemaBanter.com