• New Patreon Tier and Early Access Content available. If you would like to support AVForums, we now have a new Patreon Tier which gives you access to selected news, reviews and articles before they are available to the public. Read more.

SKY HD viewing distance

HRF1T2007

Well-known Member
Hi guys how close on sky hd would be the closest to watch from without noticing artifacts and noise

on a 42 & 46 inch tv 1080p as on PS3 i can get me noze quite close and on Sky Hd i can see some noise etc from a foot say i know you wouldn't sit that close just wandering if that was normal
 

Tony Hoyle

Well-known Member
Depends on your vision... on HD there really shouldn't be any artefacts, and noise on films is added by the producer to emulate film (although this is becoming less common as it's not popular).

Standard is 1.5* width for HD, 3* width for SD.. but as it's generally considered impractical to rearrange the room every time you change channel in general everyone picks something inbetween.

See Viewing Distance Calculator

This gives a recommended viewing distance for HD on a 46" of 5.1 feet, and a maximum of no more than 7.2 feet.
 

HRF1T2007

Well-known Member
So In SKYHD up close and personal the picture should be perfect? as on some channels ( Some Movies BBC HD)i see some noise kind of as if the channel not tuned in properly almost as the pixels of the picture are pulsating. up close about 1foot away and mainly on the dark areas it looks like a pale noise that moves ad kind of flashes, but sitting back at normal viewing it is not visible.

I have a Samsung box and not sure if a problem with dish cable or box or the is nothing wrong

On Blu ray through PS3 this does not occur
 
Last edited:

HRF1T2007

Well-known Member
You can see that the picture from very close is not super clean but the herringbone and mesh is from the camera but the speckles are not they are the ones that sem to move and pulsate up close not noticable sittting away, and not there on PS3 movies
 

Attachments

  • 100_3022.jpg
    100_3022.jpg
    115.2 KB · Views: 197
Last edited:

grahamlthompson

In memoriam
So In SKYHD up close and personal the picture should be perfect? as on some channels ( Some Movies BBC HD)i see some noise kind of as if the channel not tuned in properly almost as the pixels of the picture are pulsating. up close about 1foot away and mainly on the dark areas it looks like a pale noise that moves ad kind of flashes, but sitting back at normal viewing it is not visible.

I have a Samsung box and not sure if a problem with dish cable or box or the is nothing wrong

On Blu ray through PS3 this does not occur

It's likely mpeg artefacts arising from the lower bitrate and resolution (1440 x 1080) from HD channels using DVB-S transponders. Sky use DVB-S2 and 1920 x 1080 for the premium HD channels. Blu-ray has in comparison almost unlimited bit rate in comparison to broadcast and of course does not have the vertical artefacts arising from an interlaced transmission. Sounds pretty normal to me.
 

scarface30

Active Member
Glad I'm not the only one who notices this flickering / pulsating picture in the background on HD Channels especially on the Movie and Sports channels(funny enough not on BBC HD or ITV HD). Its as if the picture is alive in the background flicking between blurred and sharp. This is not only on my sky box but also on my FloppyDtv S2 which is especially noticeable on any personal caps I have. Checked some of my friend's caps and his don't seem to exhibit this pulsating so its not from the variable bit rate Sly use. It is the most annoying thing but for the life of me cannot figure out what is causing it. Thinking about getting a bigger dish with a top quality lnb to see if a stronger signal can sort it out.

I have a 60 inch Pioneer lx608d so it is especially noticeable.

Any ideas from the more knowledgeable as to what is causing this problem.

Thanks in advance for any advice.
 

HDCriticalFan

Active Member
Thinking about getting a bigger dish with a top quality lnb to see if a stronger signal can sort it out.

That will almost certainly make no difference whatsoever.

It's digital. If you are getting enough signal then your picture will be as good as it can get. If you aren't getting enough signal then you will have major problems - the picture will either be unwatchable or, more likely, non-existent.


With a screen as big as 60 inches then you will always be able to see "gremlins" if you look closely enough. If, as said earlier "sitting back at normal viewing it is not visible" then I would say "What's the problem ?".





Regards
 

scarface30

Active Member
The pulsating picture problem is definitely visible from a normal viewing distance in my case.

Another thought is its some kind of electrical interference from all the plugs and wires I have running behind my unit. Only problem is there not easily accessible to check because as the Pioneer is so big I can't just reach over the back and move the wires around(with big PMC OB1i's blocking any side access) and moving my unit always causes small scratches on my wood flooring due to the weight of all my equipment on it which I am not in a rush to try again.

If, as said earlier "sitting back at normal viewing it is not visible" then I would say "What's the problem ?".
 

6022tivo

Active Member
Try altering your DNE settings, MPEG reduction, Cinema settings on the TV. That noise does not look very good in the attached picture..
 

Starburst

Distinguished Member
If that was a SD image I wouldn't be impressed but of course taking a snap shot of a HD telly with a digital camera and a compressed image format(?) is never a good thing for demo purposes:)


I hate to pop some peoples bubbles but compression issues do affect broadcast HD, perhaps not the extent the mpeg2 compressed compromised SD but certainly the limitations of broadcast HD and realtime VBR compression especially as screen size increases will become more evident.
It is that area where the uber bitrates and pre-compressed Blu-ray media really gain an advantage but that is not to say that digital processing of the image of the TV is not also having a significant effect perhaps more so on lower bitrate images just as with SD CRT's and low res/bitrate broadcasts.
 

961

Well-known Member
I would suggest you try switching off any of the picture enhancers on the tv set. Noise reduction, sharpness enhancer, room lighting adjuster, motion smoother, etc etc. Ensure the backlight is set to a fairly low figure and adjust brightness and contrast accordingly.

Check all cable connects are sound and of good quality and not lying among 240v cables

Disconnect all other equipment from the tv (dvd player, games player, roof top tv aerial etc etc) while this is going on

If this does not identify a problem then it will be time to look at the sky box and the dish with the associated cabling and electronics/alignment
 

scarface30

Active Member
My Pioneer is set to ********'s LX608d recommended settings. None of that noise reduction crap is on or any other picture enhancing gremlins. I am using the top of the range Wireworld hdmi cables which I managed to get for what I see as peanuts a while back(the same price as a regular Hdmi cable) even though they list for over 200 pounds. As you suggest the only possible thing it could be is 240v electrical wires at the back of my unit which as I,ve mentioned is not easily accessible at the moment.

Thanks for all the advice.
 

The latest video from AVForums

Guardians of the Galaxy Xmas Special, Strange World, Bones and All, and Cabinet of Dr Caligari in 4K
Subscribe to our YouTube channel

Full fat HDMI teeshirts

Support AVForums with Patreon

Top Bottom