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View Full Version : Why, Oh why is BBC HD so grainy?



johnr
25-08-2008, 08:48 AM
Can any shed any light on this please?

Johnr

Keano
25-08-2008, 09:09 AM
There is no a problem with BBC HD on my sky hd box or my Octagon 918 or my DB800.

Picture quality for the games was superb.


Might help if you post some more info, ie what receiver you have.

eddman
25-08-2008, 09:26 AM
Your right johnr, I have a sony 40'' bravia 1080p and bbc hd in some places are grainy. Where as if you access to lux hd on astra 28e, the pictures are excellent. Which proves that bbc hd's quality not up the scratch.

thecaretaker
25-08-2008, 10:05 AM
There are lots of reasons why it could appear grainy to some but not others. It all depends on your box, your TV, your TV settings and what noise reduction circuits the HD picture is put through.

Sometimes, you do get a bit of grain on pictures that are shot in low light. Sometimes, the grain is intentional done for effect.

The BBCHD picture tends to be very sharp. If you have your TV settings on full sharpness with no noise reduction, you may see a grainy picture on some shots.

LuxeTV tends to shoot very bright outdoor (or well lite) shots.

As Keano said, you'll need to post much more information including what settings your TV is set at.

3tv
25-08-2008, 10:59 AM
grain is good, alot of channels use dnr so they can use more compression on an image. Older movies such as Indian Jones that was brouadcast on bbchd a few months back looked the bollock, film grain intact :) but requires more bitrate to avoid artifacts. In terms of quality bbchd is 1 of the best out there

crabber
25-08-2008, 11:46 AM
I don't think either BBC or Luxe transmit at 1920 X 1080 resolution, (only 1440) and while the pictures look good they are not as good as channels that do use full pixel resolution.

mickyas
25-08-2008, 06:19 PM
Using Panasonic Viera HD and Humax HD reciever, i have to agree with johnr and eddman, BBCHD is not very good at all, compare it with Discovery HD on Astra3 etc and you'll notice the difference straight away. Poor poor poor.
mick

johnr
27-08-2008, 12:02 PM
Thanks to all who commented.


@ Keano and Thecaretaker my setup is:


Dm800 PVR receiver and Toshiba Regza LCD TV Model 42C3035D.


Tv settings are:
1080i
Backlight 100
Contrast 100
Brightness 50
Colour 50
Tint 0
Sharpness 0
3D Colour Management off


I’ve just looked at BBC HD again and they were showing the HD previews. I must say grain was not apparent. I can only assume that the BBC from time to time must be broadcasting inferior quality HD and not just at low brightness levels. I do not think it is a function of my equipment and/or settings as the other HD channels do not show these symptoms (unless the light levels is low).

Dreamcatcher
27-08-2008, 01:22 PM
Have you tried a 720P setting john?

TonyO
27-08-2008, 01:24 PM
Garbage in !Garbage out.

The BBC is no differant to any other broadcaster, only the programmes that are sourced in HD benefit from HD transmission.

In fact not all the processes and routing in tv studios are capable of HD, most of the inferstructure is SD with only the most recently installed stuff up to HD standard.

Just transmitting an SD programme in HD does not improve it at all, in fact so far I think it makes SD look worse.

back again
27-08-2008, 01:54 PM
i find it grainy sometimes, but when i'm watching sport on the channel it seems ok,

xanadu
27-08-2008, 02:04 PM
I noticed it was grainy during the Olympics in some live studio broadcasts, but usually BBC HD is a good picture, especially on live outside events.

r.maxwell
28-08-2008, 02:19 PM
Drop to 720p and see if that makes any difference.

batman1
05-09-2008, 08:02 AM
Thanks to all who commented.


@ Keano and Thecaretaker my setup is:


Dm800 PVR receiver and Toshiba Regza LCD TV Model 42C3035D.


Tv settings are:
1080i
Backlight 100
Contrast 100
Brightness 50
Colour 50
Tint 0
Sharpness 0
3D Colour Management off


I’ve just looked at BBC HD again and they were showing the HD previews. I must say grain was not apparent. I can only assume that the BBC from time to time must be broadcasting inferior quality HD and not just at low brightness levels. I do not think it is a function of my equipment and/or settings as the other HD channels do not show these symptoms (unless the light levels is low).

No wonder things look a bit grainy, backlight at 100 contrast at 100.

Things to remember about contrast, when you are adjusting the contrast you are adjusting the white levels of the picture, not the blacks as you might think. So when you have the contrast at 100 you are effectively increasing the white level and getting greyer blacks, sounds odd I know, but this is the case. Brightness adjusts the black levels.

So with this in mind, if you then have the backlight at 100, you are increasing the brightness (the white level) and washing out the blacks, giving you greys instead, hense the grain.

Remember also, that grain could have been put there in post production, to give the effect of film.

Bonekickers, that was on earlier and being repeated at the moment has a grainy effect.

Get yourself a THX optimiser disk, such as Terminator 2, and give the video tests a run.

wowwow
12-09-2008, 05:39 PM
i watched THE VERVE Glastonbury on BBC HD on sunday and the quality was superb on my humax freesat stb and 50" LG plasma, then a jools holland proggy was on the same channel and that was grainy, so i would put it down to a possible upscale from the source rather that the equiptment..

wow:)

just for your info

Next wednesday 6:30 pm
The Verve at Glastonbury 2008 BBCHD :)

Robbie
12-09-2008, 06:06 PM
I was watching Lost Land of the Jaguar, and it was superb. No grain at all, and so sharp it was breathtaking.

I've got a Sony 40X3000 and Humax Foxsat HD receiver. I haven't changed any of the settings on the Sony, they are the same as they were when it came out of its box last week.

Bbigfoot
12-09-2008, 08:14 PM
Hi johnr,

Look at your (Colour System),
France and for that case the rest of Europe use Secam. im not
shure what the BBCs Satellite transmits in.
I had a very unstable scart (RGB) picture on my Sony LCD from Sat box.
Changed the Colour System from (Pall) to (Secam) as well as
receiving a Sharper HD quality picture it also sorted the RGB.
Thats from the Humax HDCI2000 STB.

Not shure where it is on your tv, but when you find it, it will only
light up when your Sat STB is On.
If your viewing Freeview, Colour System will be Grayed out
because it will only be receiving (UK Pall) transmission.
When you switch on your Sat box, Colour System will light Up
because it is receiving (Secam)...(Pal)...(Pall) and a load of
other types of Transmissions.
Colour system will be set to (Pall) try (Secam) first, you will
have around 5 to chose from.

BF...

Tony B2
06-12-2008, 11:26 PM
Hi johnr,

Look at your (Colour System),
France and for that case the rest of Europe use Secam. im not
shure what the BBCs Satellite transmits in.
I had a very unstable scart (RGB) picture on my Sony LCD from Sat box.
Changed the Colour System from (Pall) to (Secam) as well as
receiving a Sharper HD quality picture it also sorted the RGB.
Thats from the Humax HDCI2000 STB.

Not shure where it is on your tv, but when you find it, it will only
light up when your Sat STB is On.
If your viewing Freeview, Colour System will be Grayed out
because it will only be receiving (UK Pall) transmission.
When you switch on your Sat box, Colour System will light Up
because it is receiving (Secam)...(Pal)...(Pall) and a load of
other types of Transmissions.
Colour system will be set to (Pall) try (Secam) first, you will
have around 5 to chose from.

BF...

Surely if you're watching via a scart connection you're not watching HD?

Neither PAL nor Secam are HD either...

It is only France (in Western Europe) that uses Secam, everyone else uses variations of PAL. Some eastern European broadcasters aligned with Russia, which also used Secam, but that was more than 20 years ago.