Problem with Panasonic TX-LZD800?

[paws]

Hi there,

Firstly I will apologise for this being a bit long. I'm newly registered and followed these forums religiously before taking the plunge to buy a Panasonic TX-LZD800 which was delivered on Wednesday 18th Feb. First off, the picture quality of SD is very good, better than expected for SD, and we were blown away with the HD picture quality and the sound is excellent.

However, here is our problem. Everything seemed fine when we were connected to the normal Sky box on Wednesday. Late Thursday afternoon we were connected to Sky HD box and given a limited channel demonstration. On Thursday evening we noticed a black line, like 2 to 3 rows, across three quarters of bottom of screen, which only appeared on SD. The only way to get rid of this was to switch on picture overscan. Called Panasonic Customer Service to report problem and they emphatically said it was definitely not a problem with TV, but the fault lies with the signal coming from Sky HD box. We were also advised NOT to leave the picture overscan on permanently as this will shorten life of TV.

We then contaced Sky who sent another engineer on Sunday evening. Engineer replaced box, now problem with black and white lines across top of screen plus black line now appearing down side of screen. He changed leads and cables but to no avail and said it was likely we have a faulty TV.

Called Panasonic shop where we purchased TV and they said leave picture overscan on permanently as it is designed to compensate for SD, seeing as it is an HD set. He also said all HD TV sets on display in shop have picture overscan set to default. I asked isn't that misleading to the consumer, as the consumer will think that is how the picture would look normally? He said in his training he had never been made aware that leaving the picture overscan on would shorten life of TV. Presently waiting for him to call back.

Called Panasonic Customer Service, and this time was told that we were previously given incorrect information and that it is okay to leave picture overscan on. Here is the interesting bit, which suggests Panasonic are aware of a problem but are choosing to ignore it, he said that sometimes it can happen (i.e. the problem we've encountered), however, he then went on to put the blame straight back onto Sky and their signal.

So, we're now left having paid just over £1000 for a TV, with Panasonic and Sky playing verbal tennis, blaming each other, and we're the innocent consumer stuck in the middle, not quite sure who to believe.

Has anyone else encountered this problem with this particular TV or does anyone know who is right, Panasonic or Sky, because frankly, we're not sure what our consumer rights are in this instance?

Any insight would be appreciated

.

paws

 

[simonlewis]

Overscan should be switched on, i have mine switched on & don't have any problems.

 

[paws]

Thanks for reply. I've since spoken to Panasonic shop again and according to their technical advisor, seemingly most TV's have the picture overscan facility in order to compensate for SD. I was also wrongly advised by the Panansonic Customer Service on Friday, as it was incorrect that you cannot leave it on permanently and it doesn't shorten the life of the TV. If we'd been given the correct information in the first place, there wouldn't have been any need to call the Sky engineer again, but we are going to have the Samsung HD box replaced with an Amstrad one, as the original problem was minimal on that brand of HD box, it's much worse with the Samsung one.

Thanks again.

paws

 

[Anonymous]

Overscan should be switched off if you can avoid it. But unfortunately it's still common for broadcast video to have borders. You wouldn't normally see these but for the zero overscan / dot by dot modes on many 1080p sets. With Sky HD you should still be able to get a decent picture, even with overscan switched on. The reality though is that you're throwing away real resolution and forcing the TV's processing to work harder by using overscan, which most videophiles would agree is a bad thing.

I find it odd that one manufacturer's Sky HD box would show more of the borders than another one. They're all supposed to be built to the same specification. Your results suggest that at least one of those boxes is scaling the image more than the other before outputting it. Have you got Sky set to output 1080i? Try it on Auto instead to bypass as much of the Sky box's processing as possible.ÿ

If you can afford it, you can solve this problem by inserting a scaler that supports per input, per resolution memories (DVDO, Lumagen etc) between your Sky HD box and your TV. Set the Sky box's output resolution to Auto and the TV to dot by dot and you'll be able to tell the scaler to use overscan with SD material but not with 1080i stuff. ÿ

 

[simonlewis]

Ideally overscan should be switched on but at the end of the day it's up to the individual whether they have it switched on or off.

When watching blu-ray it should be switched off.

 

[paws]

Beaverme, I think the Sky box is set to 1080i but my husband said it's set to Auto. I know the TV is set to Auto, but we will have a look at the Sky box later to check which setting it's on. Do you work in the TV industry or do you just know a lot about them? I haven't heard of a scaler before, but I will print this off for info.

Thanks for replying.

paws

 

[paws]

SLewis, we always turn off overscan on HD/blu-ray, as the picture is absolutely perfect so we don't need it. Do you have a Panasonic LZD800?

paws

 

[Anonymous]

Hi,

This is just a hobby but I've been at it for a while and this is a problem that I've come up against myself in the past.

I've just been reading your original post again. The idea that using overscan shortens the life of your TV is nonsense. Pretty much every TV ever sold features overscan. With SD material shown on an HD TV, using overscan doesn't really do much harm, as the image is scaled anyway, either by the Sky HD box or other source or by the TV itself. The problem comes when you have a 1080 line (or 1920 x 1080 pixel) signal like 1080i or 1080p displayed on a 1920 x 1080 pixel panel. Ideally you want every pixel from the video signal to be mapped to it's corresponding pixel on the panel. That way you see the maximum resolution with the minimum of processing. If you use overscan here your TV or your source (depending on which one is doing the processing) winds up cropping the borders and scaling up what's left to fill the screen. Even with the very best image processing, this has a negative effect on image quality.

 

[paws]

Beaverme,

Okay. I just wondered as you seemed pretty clued up

. I'm still relatively new to all of this, only been looking into TV's for the last 2-3 months. When it comes to TV's, I appreciate any insight or the benefit of others experience and what you've said makes sense and is interesting to know.

We switched the Sky box to Auto and it did seem to help. Still really pleased with TV and Sky engineer called yesterday "just to keep us in the loop" to give us an update on the Amstrad box, should be fitted later this week. I wouldn't have thought different manufacturers would have made much difference, but the lines are more noticeable with the HD Samsung box.

 

[Anonymous]

Thanks,

I just this afternoon ordered a Pioneer LX5090 (my first 1080p set). I'll see what the borders look like in dot-by-dot mode with my Thomson Sky HD box and report back.ÿ

 

[paws]

Okay. I'll be interested to see what you find out

.

paws

 

[Anonymous]

Hi,

So I've had my LX5090 for a couple of days now. I haven't read the manual cover to cover but there appear to be a couple of ways to enable 1:1 source > display pixel mapping. There's PC mode which switches off overscan regardless of the source. There's also a dot-by-dot option available with 1080i and 1080p sources in AV mode. In AV mode it switches overscan back on when you change to a standard definition or 720p source (anything that isn't 1080i/p). PC mode seems to be the only way to switch off overscan with standard definition sources. In PC mode black borders are visible most of the time with standard definition material. The position and size of the borders seems to vary with the programme, rather than the channel. Even ignoring the visible borders, standard definition material tends not to look as good in PC mode. I'm assuming that the TV processes the signal differently in AV mode - it definitely looks much better.

I'm sticking with AV mode for now. If your Panny has similar modes, I'd recommend giving this a try.

Regards

 

[paws]

Hi,

Well, it's interesting that you should mention about black borders, as the Sky engineer has just replaced the Samsung HD box with a new Amstrad box and now, not only do we have a line along the bottom of the screen with SD, but also some motion blurring at the bottom of the screen and varying black borders down the sides of the picture too! A further thing we noticed on Saturday night, when we were watching a normal DVD in the blue ray player, when it came to a dark scene, there seemed to be a feint green glow in each of the bottom corners.......

We've called the Panasonic shop and they are going to come and look at it on Monday, they offered a loan TV if it has to be repaired, but we've declined on the grounds that we did make them aware of the problem only 2 days after it was delivered, so we've asked for a new replacement TV or a refund. They've since informed us that the LZD800 has been discontinued, so if they definitely find a fault the only other option would be replacement with the next new model, due out in a month, or a refund. So, we'll just have to wait and see.

I'll have a look to see if I can find PC mode.

Thanks.

paws