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Discussion Starter #1
I have a Samsung SIR-T351 OTA receiver connected to a Toshiba 46H84C via DVI/HDMI connector.

PBS HD comes in at 9 bars, but I seem to have a 'ghost shadow' trailing behind movement in scenes.

Both the STB and the display are set to 1080i.

I haven't noticed the effect on other channels.

I am thinking of switching to component cables, but I wondered if the 'wash' was unique to PBS.

I am using a Philips amplified indoor antenna.
 

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I think there might be something else going on so I've moved this thread into the HDTV Discussion forum...

I don't believe that this is any sort of OTA phenomenon because ghosting is rendered obsolete by ATSC digital broadcasting. Weird that its happening only on one channel. DVI/HDMI also should be better than component.
 

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Rogers customers seeing artifacts on PBS HD Buffalo too

With ATSC an amp won't cause any visual effects up to the overload point, at which the receiver just blanks on that channel. Also if it is the HDMI/DVI cable it would affect all channels, I believe.

Would this be some sort of artifact problem caused at PBS's end? Just wondering if there is some sort of problem in that area.

Here's a thread about Rogers customers seeing compression artifacts on PBS HD:

http://www.digitalhomecanada.com/forum/showthread.php?t=44201
 

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Discussion Starter #5
In comparison, NBC (1080i) was clearer than a bell last night without any ghosting and I'm quite sure that PBS does broadcast in 1080i as well. (FOX uses 720p and I do not notice the ghosting on it).

I do know that PBS does also broadcast 2 subchannels therefore reducing the HD bandwidth.

I'll connect the old non-amplified antenna I had a few days ago later tonight and report back.

I tried reducing the gain on the antenna which produced the same effect.

I just wondered mainly if it was the DVI/HDMI connection... obviously not if only one channel is affected.

Static images are crystal clear on PBS HD.
 

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i get the same thing... its from them not us.... my tuner is built into my tv (sanyo 30" crt hdtv)... other stations are fine
 

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I was watching the "How Art Made The World" series programme that I recorded the other night (Very Good Series) and also noticed the ghosting, as well as a bit of "jello face" (Widescreen, not HD programme).

We all need to complain to WNED that the "HD" PQ is unacceptable. (I'm on Rogers. I don't recall noticing this before, perhaps it's a recent issue). I suppose that we Rogers customers can also complain to Rogers.
 

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Here's what I just sent to WNED:

Hello, I view your channel via Rogers Cable in Toronto. I have noticed recently that there are several issues with your signal.

I am a moderator on a High Definition forum and we discuss all things HD.

The following issues have also been noted by OTA (antenna) users, so the issue is NOT with Rogers Cable.

Please see if there is something that you can do to better the picture quality, as the issues mentioned below are not present on our other HD channels.

1. Low Bitrate - I have measured the bitrate for various WNED programmes and your bitrate is significantly lower than other HD channels we receive. Most of the channels are 15-18 Mb/sec, while yours is closer to 11-13 Mb/sec.

2. This lower bitrate contributes to several compression artifacts that I (we) have noted with your signal. These are:

- Ghosting on moving images.
- "Jello Heads" on announcers that move on screen.
- Macroblocking more severe than on other channels.

I did not notice this until recently. Is there something that you have done that could be causing these issues?

Thank you for listening:

57
[email protected]
 

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I also get the ghosting & 'jello face' on PBS, using my HP 5020 DLP. I've been fiddling with settings for a while, trying to remedy it. Since everyone else always comments on how good PBS looks, I figured it must be a problem at my end.

All my other channels look fine. Those two issues on PBS make it pretty much unwatchable for me, as things like that really irritate me. My wife didn't even mention it, till I pointed it out.
 

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Discussion Starter #12
57 said:
Here's what I just sent to WNED:
Did you get the same response I did... nada ?

There was a wonderful Springsteen performance last night, beautifully shot, but unfortunately, compression artifacts really distracted from the show.

I've noticed the odd audio dropout as well.
 

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We had MASSIVE jello head and ghosting on PBS with a Rogers 3250HD box....no over the air.
It was the only channel in the R%ogers HD lineup that was doing it.
Was watching the "Piano Man" show when it was super bad. And this is when I was setting up the one Home Theatre room at the store.
 

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This is definitely something new. I watched the Cousteau Shark programme and the ghosting was really bad. Every time a shark swam past, there were a half dozen "ghost trails" following the fin.

It was definitely not like this a few months ago when we watched the first Cousteau programmes. If I don't hear back in a day or so, I'll write again.
 

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Discussion Starter #18
57 said:
This is definitely something new. I watched the Cousteau Shark programme and the ghosting was really bad. Every time a shark swam past, there were a half dozen "ghost trails" following the fin.
I watched that too. Stunning photography as displayed by near static images.

It is so unfortunate to ruin it with overcompression.
 

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Discussion Starter #20
Hmmm, I got this today:



Sorry it took so long to get back to you. We have very recently received a couple of more complaints of this nature - smearing or ghosting with fast motion. This feed comes directly to us from PBS,
and the best we can tell is that they may be having problems with shows that were not originally filmed in HD. They "upconvert" these shows, and it appears that the upconversion process may have
some issues with fast motion. To be honest, we really haven't seen the problem here so we have to assume that it is only on occasional shows.

We haven't changed our subchannel lineup or bandwidth parameters in over a year, and this appears to be a recent problem, so I don't think this is an issue. FYI, we use a system that dynamically
allocates bandwidth to whichever channel(s) need it most at any given time, with the HD channel as a priority, so this shouldn't be a problem for all but the most demanding video.

We'll keep an eye on this and if we can catch it in the act we'll be able to determine if it's coming from the source.

Best regards and thanks for viewing!

Joe Puma
Director of Engineering and Technology
Western New York Public Broadcasting Association
 
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