I wasn't sure if this was a calibration issue, just the way some "weaker" HDTVs are, or shoddy Comcast bandwidth..

But often on some HD stations.. or if you come closer to the screen on alot of them, you can see a great deal of pixelation.. I'm guessing this is normal and a bandwidth issue..

I run my comcast box at 1080i (not 720p).. I have a Samsung HL-T6176S 61" slim DLP where i notice this.. I also have a 24" 1080P Westinghouse PC/TV/monitor.. and you can see it there too..

They were playing Lord of the rings (Vol II) on TNT HD.. I could see the pixelation in the darker areas alot at a times (on the 24" sitting 18" away) and on the 61" if you look closer..

Any thoughts on this.. or is the norm?

I'm running HDMI on the 61" and component on the 24" (at same time from same dvr).


Also.. if i were to stick in an HD-DVD of the same movie at 1080p or even 1080i.. would I still notice this?

Thanks

Pixelation can take may forms, and have many causes. First of all, some degree of (I'll call it) "blockiness" is inherent in MPEG compression, which is used in virtually all HD TV systems. If you are seeing major areas of the picture "break-up" with blocks of dramatically different color (usually white), you are probably seeing the digital signal dropping out. That could be due to low signal levels on your cable system. If, what you are seeing is more subtle (you referred to pixellation in the darker areas) it could be in the original encoding (on TNTs end in your example), or excessive compression by the distributer (Satellite needs to compress too). HD-DVDs & Blu-Ray use less compression (but it is still there).

While calibration really has nothing to do with these artifacts, the use of various image "enhancments" can well exaggerate these. And if you are noticing this largely in the dark areas, that suggests that the various "black detail enhancements" in use today could well be making things that are not noticable in properly adjusted sets, quite noticable on yours.

Pixelation can take may forms, and have many causes. First of all, some degree of (I'll call it) "blockiness" is inherent in MPEG compression, which is used in virtually all HD TV systems. If you are seeing major areas of the picture "break-up" with blocks of dramatically different color (usually white), you are probably seeing the digital signal dropping out. That could be due to low signal levels on your cable system. If, what you are seeing is more subtle (you referred to pixellation in the darker areas) it could be in the original encoding (on TNTs end in your example), or excessive compression by the distributer (Satellite needs to compress too). HD-DVDs & Blu-Ray use less compression (but it is still there).

While calibration really has nothing to do with these artifacts, the use of various image "enhancments" can well exaggerate these. And if you are noticing this largely in the dark areas, that suggests that the various "black detail enhancements" in use today could well be making things that are not noticable in properly adjusted sets, quite noticable on yours.

I figured it was the case of the feed more so than anything else..

Though.. tonight watching Sunday night football on NBC.. i noticed a little pixelation, you had to look for it.. on the 61".. so i decided to go into the other room where i have the Comcast feed going as well (same time).. via component in there (HDMI on the 61).. i could see alot in that room on a 24" HD Westinghouse screen.. much more noticeable.. same feed...

So I decided to try switching to hdmi, so i brought the LCD into the other room, plugged in the HDMI and there was significantly less pixelation and blockyness.. I thought most said they couldnt see a difference b/w component and hdmi (although here i was using both at once from same DVR, not sure if this matters, and on two different tvs but it was visible).

So I decided to try switching to hdmi, so i brought the LCD into the other room, plugged in the HDMI and there was significantly less pixelation and blockyness.. I thought most said they couldnt see a difference b/w component and hdmi (although here i was using both at once from same DVR, not sure if this matters, and on two different tvs but it was visible).Pixellation problems should be no different with component or HDMI - HOWEVER, the user settings were likely different between the two. I am even more convinced that the problems are due to your user settings.

Pixellation problems should be no different with component or HDMI - HOWEVER, the user settings were likely different between the two. I am even more convinced that the problems are due to your user settings.

Perhaps.. though i did try to tweak some of the settings, didnt help a whole lot.. its harder on the 24" to calibrate, as I dont have a DVD player hooked up to that one.. I do have the Avia test disc, i was going to run it on the bigger tv.. i'm assuming its straightforward and you just follow through and adjust (i have a blue filter too). Originally I calibrated using the CC provided cheesy calibration disc, but my calibration settings were alot different than what was posted in the Samsung thread as being the "best". I realize there is some wiggle room there though.

In the beginning days of HD around here (san francisco bay area), we "helped" the HD stations and the cable providers ensure that they were delivering full bitrate HD streams. If you're getting reduced bit-rates, you'll see pixelation, even in HD broadcasts.

Showtime HD and HBO HD are notorious for providing reduced bitrate streams to the cable systems. "HD" showings of Daredevil or any of the Matrix films suffer considerable from reduced bitrates. Just try to watch the scenes with flashing lights or heavy rain scenes. They are a horrific mess of pixelation!

The only way to really check this is to analyze the bitrate in the streams. Sometimes there'll be a local HD yahoo group (SF has one) and some folks do do this. It's been verified that comcast (local cable provider) is delivering exactly what the locals do in HD OTA.

so bottomline is that if you're seeing pixelation on HD broadcast on cable it could be the cable system or a calibration issue or both. Discovery HD and ESPN HD tend to be quite good as do the national HD network broadcasts (primetime). If you see pixelation on these broadcasts, there could be an issue with what the cable system is delivering. If you have access to OTA HD, you can do an A/B comparison. OTA HD and Cable HD of the same content (not DVR'd) should be the same. If they are not, then the issue is the the Cable HD.

Do you see pixelation with DVD source (SD, upconverted, HD-DVD, Blu-ray)? If so, then I suspect a display issue.

Hopefully I had at least one good idea that you can try in this post.

Best,
jeff

In the beginning days of HD around here (san francisco bay area), we "helped" the HD stations and the cable providers ensure that they were delivering full bitrate HD streams. If you're getting reduced bit-rates, you'll see pixelation, even in HD broadcasts.

Showtime HD and HBO HD are notorious for providing reduced bitrate streams to the cable systems. "HD" showings of Daredevil or any of the Matrix films suffer considerable from reduced bitrates. Just try to watch the scenes with flashing lights or heavy rain scenes. They are a horrific mess of pixelation!

The only way to really check this is to analyze the bitrate in the streams. Sometimes there'll be a local HD yahoo group (SF has one) and some folks do do this. It's been verified that comcast (local cable provider) is delivering exactly what the locals do in HD OTA.

so bottomline is that if you're seeing pixelation on HD broadcast on cable it could be the cable system or a calibration issue or both. Discovery HD and ESPN HD tend to be quite good as do the national HD network broadcasts (primetime). If you see pixelation on these broadcasts, there could be an issue with what the cable system is delivering. If you have access to OTA HD, you can do an A/B comparison. OTA HD and Cable HD of the same content (not DVR'd) should be the same. If they are not, then the issue is the the Cable HD.

Do you see pixelation with DVD source (SD, upconverted, HD-DVD, Blu-ray)? If so, then I suspect a display issue.

Hopefully I had at least one good idea that you can try in this post.

Best,
jeff

Thanks for the reply.. I tried my Avia DVD disc, didnt notice any real pixelation when i tested it for maybe 1 minute (need to revisit this one too).. Side note: I did notice that the tv info said 720x480 for the resolution.. I have a 1080i/720p upconverting Panasonic DVD player.. I thought it should have said something a bit higher, but didnt see any options in the DVD system setup menu.

Also.. I set my DVR Comcast box to 1080i.. not 720p.. I really couldnt see a difference between the two.. I'm guessing this is fine as well.

I dont have a BD or HD player just yet.. but i think by next year I'll be grabbing that Samsung Dual format player when the price drops :)