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« Axis Of Evil Update | Main | 2005 In Space »

Video Bleg

Any HD geeks out there?

I'm looking at this television, which is on sale at Costco for less than a grand.

It looks good, but I found this one review that's giving me a little heartburn, because we have DirecTV, and planned to upgrade to a triple LNB dish and new HD TIVO receiver.

It is an excellent set for HD OTA and regular definition satellite receiver. But I recently upgraded to an HD receiver for DirecTV and found out it doesn't have the capability to keep up with the HD satellite receiver. There is a phenomena called macroblocking that occurs since the digital picture cannot be translated properly. Defined - it is an awful picture on the 480i channels, which means about 95 of my programs looked awful.

I searched all over the web, and couldn't find any other reference to this problem. Is it a real one, or is this an isolated problem for this one reviewer, either because (s)he didn't understand how to set it up, or there was something defective about that unit?

Posted by Rand Simberg at December 22, 2005 02:41 PM
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If you have $3500, pop for a 1080p rear projection unit.

Posted by Sam Dinkin at December 22, 2005 03:13 PM

Macroblocking can occur with any HD system, but especially with satellite systems during rain due to a degraded signal level. But the satellite receiver should be doing most of the work in decoding the satellite HD signal. The TV should faithfully represent what is passed to it. The problems that I have seen at home have been related to glitches in my cable signal, not the tv.

That said, there is a potential for problems with hardware compatibility. The HD standard has a lot of options and different vendors implement them differently. I am currently experiencing this phenomenon at work.

Posted by Mazoo at December 22, 2005 03:32 PM

You should be fine. Actually the CRT monitors are better than the much ballyhooed DLP monitors. DLP's have a better chance of burn in and reproduce colors worse than CRT's. The color, especially the dark colors are great on that monitor. I have a 55 inch CRT from Toshiba with the Tivo HD Receiver and Direct TV and it is an awesome thing. Prepare to never leave your living room.

Posted by Jim P at December 22, 2005 03:37 PM

Oh, and I have never had the macroblocking problem. The HD is crystal clear and the digital picture is great.

Posted by Jim P at December 22, 2005 03:39 PM

I have the exact same TV except in the 48" size and do not know what that person is talking about. The only think I can think of is the TV having to do antialiasing on the signal when upconverting to the 1080i display of the TV. The problem here is the crappy signal sent by DirecTV. HDTV's show what they get. If the signal resolution is bad, it shows up on a HDTV where a regular analog TV will smear the picture and make it look better due to nature doing the antialiasing for free. The only draw back on the CRT HDTV's that I know of is that the cathode guns need to be realigned from time to time through the convergence setting on the TV and then the electronics store I bought my TV from said that every two or three years the cathode guns need to be adjusted by a technician. Other wise I think you have no worries for the price.

Posted by Gus at December 22, 2005 04:35 PM

Sam, if I had $3500 to spend on a teevee, I wouldn't ask the question...

Do you want to buy me one for Christmas? ;-)

Posted by Rand Simberg at December 22, 2005 05:12 PM

DLPs do NOT burn in. At all. Ever.
CRTs, plasma, and LCDs can all burn in. CRT RP TVs are a dying breed and cost a bundle to fix if the tubes go (as they do).
Right now the sweet spot in HDTV is a DLP with an ISF calibration. Pop for the three-chip DLP if budget allows.
Much good info here:
http://www.primediahometech.com/dlpseeit/

Posted by Toren at December 22, 2005 07:25 PM

Yeah, the digital mirror devices are pretty nearly magical- think of a college stadium placard cheering section shrunk onto a chip. When I worked at a probe card manufacturer in the 90s, we sold some to TI, but the techs there would occasionally forget to lift the probes off the wafer before scanning to the next device... somebody at TI still has about seven million years' worth of bad luck coming to him.

Posted by Doug Jones at December 22, 2005 07:54 PM

Most home theater experts will tell you that CRT quality properly calibrated is much better than a DLP. It really all comes down to space issues for the reason you don't see CRT's as much and the prices are so low. And yes, I misspoke, DLP's don't suffer burn in but their bulbs do DIE quickly, quicker than CRT's do and CRT's are cheaper. You can expect to change out the bulbs every couple of years which is expensive. It is also pretty unlikely that a CRT monitor, especially these newer ones will burn in. If they are going to burn in, it is likely in the first 100 hours. Also another drawback to DLP's is the "rainbow effect" (where you can see streaks of color) fromt the color wheels they use. Newer ones are better about that.

Posted by Jim P at December 22, 2005 07:58 PM

I read a few month's ago that DirecTV was going to be changing how it encodes its HDTV signal (in order to squeeze more channels in). The up shot of this was that present DirecTV HD recievers would not work for HD. This was obviously very upsetting to those that spent $700 for the HD DirecTV tivo.

Can anyone confirm this or provide better info?

I suggest you investigate that issue closely before you put the money down on the HD Tivo.

Are we talking Tivo brand, or tivo-like DVR?

Cheers

--Fred

Posted by Fred K at December 22, 2005 10:04 PM

Jim, DLP bulbs do die more quickly than CRTs, but a DLP has only one bulb, not three CRTs, and the CRT replacements are 3 to 5 times as expensive, not cheaper.
Yes, CRT projectors are still the gold standard in home theater, but they are very, very expensive.
The newer DLPs have no rainbow effect.

Posted by Toren at December 23, 2005 10:23 AM

Here is probably everything anyone needs to know about DLP chip construction and utilization.

CRT is a proven technology with nearly all the kinks worked out compared to the newer HD technologies which have shown to maintain life spans on average of 5 years. One will sacrifice size and weight going for CRT over DLP, Plasma, LCD. If one needs to have something that hangs on a wall I'd go with LCD. Plasma is extremely easy to burn in and many models lose brightness after a year or so - LCD do experience similar issues but not nearly as bad. DLP is a mechanical device and can experience dead pixel issues or total loss of picture at some point.

Some HD set models do a better job at reproducing the 480i content then others. This is an important consideration since most the broadcast content is still in this format. When you get into HD broadcasts then your start to run into resolution and proportional sizing issues much the same as one would encounter adjusting the display properties on your PC. Manufacturers employ different pull down, filtering, and Inverse Telecine methods that can smooth out MPEG artifacts. Most HD models faithfully reproduce a satisfactory HD signal image dependant upon signal quality.

Sony and Toshiba tend to lead in terms of overall satisfaction. JVC is a good model to choose from when it comes to reliability. When it comes to Rear projection TV sets reliability is an important consideration. On average rear projection sets are about twice as likely to encounter a malfunction when compared to a conventional picture tube. It is still early to tell for the newer technologies but they appear to be even more prone to repair issues then CRT based rear projection.

Your probably not going to find a set that rates well in DVD and S-VIDEO picture quality in the 1000-1800 dollar price range. I would probably look more seriously at the Sony Models then the Pana-sonic. Something like the:

Sony KP-51(W)S520

Posted by Josh Reiter at December 23, 2005 11:28 AM

As some posters have mentioned, the problem is the compression algorithm that the supplier uses and the decompression algorithm. This is not just an HDTV problem. My Adobe and JASC photo processors handle JPEGs differently. Most pics will look fine on either, but sometimes one pic will block up on one, another pic will block up on the other.

It's got to be a real problem with moving pictures because of the time constraint. It's a wonder that they look as good as they do.

Posted by Bernard W Joseph at December 23, 2005 11:43 AM

Torg,

Thanks for the comments, but DLP's do experience the rainbow effect, but it just isn't as likely you will notice it. I realize that is a bit like "if a tree falls in the wood, does it make a sound", so it really doesn't matter as much. AS for the expense, rear projection CRT's like this are inexpensive and one probably has to do a space vs overall cost analysis to determine which way to go in the end.

Posted by Jim P at December 23, 2005 02:17 PM

I have a Sony GrandWega, which is LCD Projection but not DLP. The picture is awesome, even 70 degrees off angle.

The problem with macroblocking is the native display properties of the TV. Common display settings are 480, 720, 1080 (interlaced or progressive in either). In a simplistic example, the set may support 1080i, but really only shows 720 (such as original DLP sets). Therefore, it dithers the extra pixels into surrounding pixels. If the coding is poor, the picture quality will suffer. This of course is much worse when dithering a 480 to 720! However, 720 is usually the resolution not natively available to most CRT sets.

Interlace and Progressive only refer to the number of lines refreshed during a cycle. Interlace refreshes every other line per cycle, while Progressive refreshes all lines per cycle. Thus, Progressive is considered the best.

My experience, 3 years ago, is that Hitachi makes the best CRT projection HDTVs. They were the first with 1080p. My sister got a 57" Hitachi and it is awesome. However, my 42" Sony LCD Projection is much easier to move.

Finally, if you go CRT projection, check into the extended warranty. Not for quality purposes, but rather some warranties include relocation services. In other words, if you move, they'll send somebody out to move that heavy weight console for you.

Posted by Leland at December 27, 2005 06:27 AM


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