Question about pixilation ...

[Pyrophoric]

I see what I consider to be two types of this with my 522 from Dish but I am trying to figure out which, if either, is supposed to be there and which is the "problem" pixilation...

One form of this pixilation is always there.. I can see the tiny pixels of the images. This pixilation is more noticable around slow/steady moving objects (i.e. people) on tv.

The other form is usually when the channel is being changed, loss of signal, or sometimes even when recording. It is much!! large pixilation yet not as annoying as the first because this form is rare.

Atm I am going on the assumption that the first form is not only normal but is the diff. between digital and HDTV but I wanted to know for sure if I am right. If I am right then I need to get HDTV SOON! because the notice of small pixels is getting to me.

Also, I never noticed the first form(small pixels) before and that might be because I just switched from coax cable to s-video. When I was on coax the picture was just overall so aweful that if there were pixels I prolly wouldn't ever notice em and now being on s-video it is soooo clear that I am just seeing them for the first time.


Anyways, thx for any and all info

 

[Mark_AR]

What kind of TV are you viewing.

If it is an older set, it may just be 'halo' or something of that nature. Its tough to say without more info.

Pixelation is more of a blocky image. It might be several blocks in a general area, or in any of a random placing on the screen that only lasts a moment.

 

[Pyrophoric]

The TV is only a year or so old. Its a Sony.

 

[TuxCoder]

The first form you describe is merely the primary negative side effect of high MPEG compression--termed "artifacts". The encoder is "simplifying" the picture (the frames, and the motion among frames) to use up less bandwidth. Thus they cram more channels into the same space. And yes, that is typically a good differentiation between plain-old standard definition digital televistion (SD DTV) and true high definition digital television (HDTV). Though many providers compress their HD offerings, it's nowhere near the compression that the SD channels get. Off-the-air (OTA) HD is usually not compressed very much.

The second form you describe (termed "blocking") is caused by a number of factors. If you get it frequently while just watching TV and not changing channels or anything, it could be a sign your signal is weak. Your dish might need pointed better, or there might be rain or heavy moisture (thick clouds, etc.) blocking some signal. Some times, though very rarely, it's just a hiccup in E*'s encoders, or possibly, your receiver's decoder. I wouldn't worry too much about seeing it while changing channels though. You're interrupting one MPEG stream to switch to another mid-stream. Your receiver should blank the screen appropriately to mask the effects of this, but maybe it's missing some of it.

 

[TuxCoder]

The TV is only a year or so old. Its a Sony.

I'll add, there have been numerous reports of picture quality problems with Sony TVs and digital TV signals. You might want to search this site for the related threads.

 

[earth station]

If it's the pixelation on recordings of the 522, it's a known defect with the machine that has only one fix - DIRECTV Tivo!

If it's not recordings, then you must have an HDTV. Oregon has plenty of rainfall and I've never lost signal. 522s display lower signal levels than 510s, 311s, etc... Mine is 102 on the high-end, 90 on the low end, not including local spot beam (124). This would be the equivalent of 115-100 on a 311 or 510.

Just for kicks, I peaked in my dish only half way one time to see if the signal would drop out around 35-40 like on 311s, etc... and sure enough it does. Engineering says the 522s have a different threshold, which is bologna, cause if it did, i'd lose signal in the 20s instead of the 30s. I've never understood why they produced a box that carries lower signal strength, especially with the whole issue of rainfade. But I guess it goes along with them making anti-cable ads at the same time they raise rates.