dish, motion artifacts & plasma vs led

[drewg]

While I was out of town on a business trip, my friend finally upgraded from SD to HD. They've got a 47" Vizio "Razor" LED TV. I don't remember the exact model, I think they paid something like $800 for it, and its at least 120Hz. Its connected to a new Dish VIP 612 DVR. It is his first HD tv. Anyway, they invited me over to help them set it up because, frankly, it looks horrible and they're really disappointed.

Using Dish TV as an input, there is a *lot* of compression artifacts, and macroblocking (friends wife talked about the TV having to "catch up"). Any area of motion on the screen is basically unwatchable. This even impacts the lip movements of people talking. Sports are unbearable. I spent 1/2 hour or so going through the TV's settings, playing with sharpness, contrast & noise reduction settings, and cinema/motion setting, and I couldn't make it much better.

I then hooked up an OTA antenna, and we flipped back and forth between antenna and dish while watching a local station. The ATSC version was much better, but still nowhere near as good as my HD300 & my 3 year old 46" Sony 1080P 60Hz panel.

They're asking me for advice as to what to do, and I'm not really sure what to tell them. My gut reaction is to have them take the TV back, and get a similarly priced LG plasma (also because their viewing angle sucks, which is much worse for LCD/LED). Am I right in guessing that a plasma will do a better job in "smoothing" things out?

I've prepared a USB stick with some sample SageTV recordings & videos for them to take to the TV store & compare to their TV. I'm thinking that just giving them a way to watch clips of various things (including SD kids shows) will help them choose.

Thanks,

Drew

[Taddeusz]

This doesn't sound like it has anything to do with the TV itself. Sounds like Dish is just over compressing the video. I say this because the Dish box is what decompresses the video. The TV has nothing to do with compression artifacts and macroblocking. If the TV is connected with HDMI it is receiving a raw uncompressed video signal from the box.

[drewg]

Originally Posted by Taddeusz

This doesn't sound like it has anything to do with the TV itself. Sounds like Dish is just over compressing the video. I say this because the Dish box is what decompresses the video. The TV has nothing to do with compression artifacts and macroblocking. If the TV is connected with HDMI it is receiving a raw uncompressed video signal from the box.

That's what I thought, until we looked at OTA & took the dish box out of the picture. We saw more compression artifacts when watching OTA via the TV's internal tuner than we did watching the same show via an HD300 on my older Sony. Its so hard to draw any conclusions because we have apples, oranges, and bananas...

My impression was that "older technology" TVs (like CRT & Plasma) are better at smoothing things out, and making compression artifacts less noticeable.

Drew

[drewg]

Fiddled with their TV a bit more this evening, and got OTA looking good. Then I realized that the HD that their Dish box was giving the TV was stretched. Now they seem reasonably happy..

Drew

[Fuzzy]

If you're seeing a lot of blocking on the dish network channels, it may actually be a signal issue from the dish. A weak signal will cause corrupted packets, causing loss of information, which will cause some blocks to remain unchanged until the next I-frame comes along. This may be what they are talking about with it 'catching up'.

[ccsmoke]

I agree with Fuzzy. You should be able to tell the signal strength in settings menu of the receiver. You also want to visually look at the install to see if the dish is secured or moving at all. Also look for branches that could be in the way of the signal. Sadly even with the best signal you can get macroblocking in a hard rain for an example.

As for calibrating the TV...I would use a Blu-ray player or DVD Player and use a calibration disk to at least get in the tv in the ball park. Not only will you get a better picture...in some cases (plasmas) you can extend the life of the tv and lower electrical use.

[drewg]

Originally Posted by Fuzzy

If you're seeing a lot of blocking on the dish network channels, it may actually be a signal issue from the dish. A weak signal will cause corrupted packets, causing loss of information, which will cause some blocks to remain unchanged until the next I-frame comes along. This may be what they are talking about with it 'catching up'.

That makes sense. I guess I'm more used to weak OTA signals, where the corruption tends to be very apparent. Does satellite corruption act this way..?
The problems they were having really looked more like Dish having bandwidth issues (eg, too much compression). It didn't help that the TV seemed to be set up to look really eye popping with 1080p Blue Ray content (all edge enhancing things were all turned up, which made any imperfections very apparent).

Next time I'm over, I'll certainly check the signal strength. What is considered "good" for Dish?

Thanks,

Drew

[Fuzzy]

I know I have never seen obvious macroblocking on and Dish HD station. And yes, the poor signal blocking from Dish's HD channels will not look the same as that of the OTA channels, simply due to the different compression system used (OTA = MPEG2, DishHD = H.264). 5Mbps H.264, 1440x1080, is what most Dish channels are broadcast in, and most should find that quality quite acceptable.

[stanger89]

I can't really add much but I've got a Samung 46B6000 in my living room (LED LCD) and i haven't noticed anything like that with my Dish setup. You might want to go through and try and disable some of the "enhancements" in the TV's settings. Maybe try looking for a movie, or cinema preset (or do a search on AVS for calibration/setup tips).

[ccsmoke]

Been a while since I had dish, but 90 or above is what I would shoot for. 80 and below can cause issues like your having. I think in settings in the receiver you should have a test signal strength (might be under troubleshooting). You can change transponders also. I would also ask where is the OTA antenna. Curious if it is on the dish itself. If both the dish signal and OTA are low signal...could be cable length, spliiters, or cable pinched (stapled).

http://revision3.com/hdnation/hdcalibration#rev3Player at 13:41 is good video how to on basic TV calibration.

DVD/Blu-Ray with THX logo and some Disney disks should have basic video tools on them.

[stanger89]

Originally Posted by ccsmoke

I think in settings in the receiver you should have a test signal strength (might be under troubleshooting). You can change transponders also.

I think it's Point Dish, in the installation menu.

[drewg]

You guys are probably right about it being the signal levels. The first time I was over there, it was windy & the problem was bad. The next day, it was calm. I looked at the dish itself, it it is mounted to an incredibly flimsy pole which seems to sway in the breeze.

Haven't been back since, so I haven't looked at the signal levels.

Drew