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panasonic TH42PZ70 - help changing the picture

billybug

Standard Member
Just set up the TH42PZ70 - everything fantastic, except, when comparing to other tv's in the house, the top inch or so of peoples heads seem to be cut off - i.e the picture size seems to be a little big - could do with sort of zooming out a fraction, so that all of peoples heads fit the screen.

Another example is on channel 5 - the FIVE logo is right at the top of the screen, but on other tv's its a small way in from the top of the screen.

Does anybody know if there is a way of changing this?
 
D

darkmagi

Guest
Not sure how you do it on your tv but there should be a picture size button on your remote on my samsung it says p.size look for this & it should run through the picture size options try it on auto.

Hope this helps......... :)
 

billybug

Standard Member
Thanks,

ive tried changing the picture size/aspect ratio - neither auto nor 16:9 makes any different - they both suit the programme being shown - but just seem to cut the top of the pictue off!
 

google

Distinguished Member
If you change it to off you may notice a difference in the aspect ratio which may solve your problem?
 

billybug

Standard Member
Having got the initial problem sorted - there is a slight hiccup. When I go to AV1 - my Topfield Freeview/hard disk drive (only really to watch recorded programmes). The picture size is still reduced slighty (so peoples heads fit on the screen), which is good - but at the very top of the picture, there are a serious of lines _ _ _ _ _ _ _ _ like this, starting in the top left and continuing across horizontall for some distance.

When I put the picture overscan back to 'ON', the picture size increase slightly and the lines disapear.

Any ideas what this is and how to get rid of it?
 

Ian Dudley

Active Member
Having got the initial problem sorted - there is a slight hiccup. When I go to AV1 - my Topfield Freeview/hard disk drive (only really to watch recorded programmes). The picture size is still reduced slighty (so peoples heads fit on the screen), which is good - but at the very top of the picture, there are a serious of lines _ _ _ _ _ _ _ _ like this, starting in the top left and continuing across horizontall for some distance.

When I put the picture overscan back to 'ON', the picture size increase slightly and the lines disapear.

Any ideas what this is and how to get rid of it?

I think you have a problem with you PVR, rather than your TV. Those lines are supposed to be there (it's teletext or something like that), but would normally not be visible as the overscan hides them. Thats kind of the point of overscan and most TVs do it automatically and it cant be switched off.

You should only want or need to switch off overscan when viewing from a known controlled source, i.e. a DVD player or HD/BD player. For viewing off air stuff, overscan should normally be set to on as otherwise you will see a variety of odd noise at the edge of the image.

If you need to switch off overscan in order to see the full picture from your PVR, something isnt right. Broadcasters don't put needed parts of the image in the overscan area as 99.99 percent of TVs wont see it due to overscan!.

Firstly, make sure the PZ70 isn't set to Auto, this can do some weird things as it has a variable zoom which tries to detect the optimal way to view 4:3 images. But I somehow don't think that is the problem you are having as you can't switch off overscan in auto mode.

It sounds to me like your source (i.e. the PVR) is zooming the image, rather than the TV. I'm not familiar with topfields, but I'd go and poke about its display settings.

If you view the same channels on the PZ70s internal DVB receiver, do you have the same problem?
 

billybug

Standard Member
No the problem with the lines _ _ _ _ _ doesnt occur on any channel viewed directly from the PZ70. However, thats were the initial problem of missing the tops of peoples heads off came from.

When comparing the picture on the PZ70 (not viewed through the topfield - this is directly form the PZ70) with other TV's in the house, it became apparent that the very top bit of the picture wasn't being shown. I.E. the very tops of peoples heads and also for example the channel FIVE logo was closer to the top of the screen on the PZ70 than it was on any other TV. That's when I was advised to see what happened if I turned the picture overscan to 'OFF'. Doing this solved the problem, the PZ70 now shows as much (or may be even a tiny bit more) than the other TV's in the house. However, it was sometime after cracking this, that I went to AV1 (the topfield) and noticed the lines.

Do you think that when viewing directly from the PZ70, that I shouldn't have to switch the overscan to 'OFF' in order to get a correctly sized picture? In which case, could there be a problem with the set?

I can solve the lines problem on the AV1 (topfield) by simply turning overscan back to 'ON'. Its just a pain in the backside having to change it everytime i go to AV1 - plus the top of head problem arrises when it's turned back to 'ON'.
 

Ian Dudley

Active Member
No the problem with the lines _ _ _ _ _ doesnt occur on any channel viewed directly from the PZ70. However, thats were the initial problem of missing the tops of peoples heads off came from.

When comparing the picture on the PZ70 (not viewed through the topfield - this is directly form the PZ70) with other TV's in the house, it became apparent that the very top bit of the picture wasn't being shown. I.E. the very tops of peoples heads and also for example the channel FIVE logo was closer to the top of the screen on the PZ70 than it was on any other TV. That's when I was advised to see what happened if I turned the picture overscan to 'OFF'. Doing this solved the problem, the PZ70 now shows as much (or may be even a tiny bit more) than the other TV's in the house. However, it was sometime after cracking this, that I went to AV1 (the topfield) and noticed the lines.

Do you think that when viewing directly from the PZ70, that I shouldn't have to switch the overscan to 'OFF' in order to get a correctly sized picture? In which case, could there be a problem with the set?

I can solve the lines problem on the AV1 (topfield) by simply turning overscan back to 'ON'. Its just a pain in the backside having to change it everytime i go to AV1 - plus the top of head problem arrises when it's turned back to 'ON'.

Something weird is going on here. Overscan should only crop around 3% of the picture, right around the screen, and as broadcasters know this will happen it shouldn't cut off anything that is important to view. It certainly shouldn't be cutting people's head off!

I leave overscan on all the time, as otherwise you see various white or green bars at the side of the screen, exactly as you are describing. This isnt a fault, its extra information (teletext, subtitles or that sort of thing) which is transmitted in the 'hidden' area of the screen. The only time I switch off overscan is when watching DVD's, as they don't have that extra info.

Note, the reason to switch off overscan shouldn't be to se more picture, its to avoid the TV re-sampling the image and therefore adding an extra processing stage which reduces the quality. You shouldn't really see any difference worth worrying about in the amount of picture you are seeing.

All I can think of is that the overscan on your PZ70 is somehow a bit faulty and is cropping a lot more than the 3% it should be doing. Bit of a long shot though. Possibly this is something that can be adjusted in the engineers menu, but I wouldn't touch anything in there unless you know what you are doing. Check with more knowledgable people than me on here before you poke about in there!

Might be worth taking a couple of pictures and posting them up so other owners can compare what you are seeing with thier own PZ70s. Try taking some pictures of something that is regularly broadcast with the same image, e.g. BBC news or something like that, so we can tune into the same program and compare.
 

billybug

Standard Member
Ian, thanks so far.

Just to provide a bit more infor - it's not like the whole of the head is being chopped off! Its just the very top of it - and I suppose the easiest way to describe it is the TV Channel Logos - for instance the channel FIVE logo is deffinatley closer to the top of the screen, than it is on the other TV's. The whole of the FIVE logo is still shown on th pz70, but it is very close to the top of the screen. Where as on other TV's there is a larger gap between the top of the FIVE logo and the top of the picture.

One further point, there is a noticeable difference in the amount of picture shown on the screen when overscan is turned off - i'd guess more than 3% - but I will have a closer look this evening.

So far when viewed directly on the PZ70 (with overscan - OFF) I have not noticed any lines, squiggles or distoration around the screen edges - so at least that is good news.
 

Ian Dudley

Active Member
Ian, thanks so far.

Just to provide a bit more infor - it's not like the whole of the head is being chopped off! Its just the very top of it - and I suppose the easiest way to describe it is the TV Channel Logos - for instance the channel FIVE logo is deffinatley closer to the top of the screen, than it is on the other TV's. The whole of the FIVE logo is still shown on th pz70, but it is very close to the top of the screen. Where as on other TV's there is a larger gap between the top of the FIVE logo and the top of the picture.

One further point, there is a noticeable difference in the amount of picture shown on the screen when overscan is turned off - i'd guess more than 3% - but I will have a closer look this evening.

So far when viewed directly on the PZ70 (with overscan - OFF) I have not noticed any lines, squiggles or distoration around the screen edges - so at least that is good news.

One question, the other TVs you are comparing to, are they all widescreen? Some broadcasters when transmitting the WS image on cable or freeview crop the top rather than putting out the extra info to the side. Especially with content that was originally recorded in 4:3. e.g. if you watch teletubbies on Cbeebies in widescreen, during the end credits half the credits are missing at the bottom.

that's just how it's broadcast and until everythign is recorded in WS format there probably isn't much you can do about it.

Other than that, you must have an unusually large overscan on that set. The question is whether all PZ70s have it or just yours.
 

vipergrm

Well-known Member
I'm pretty certain this has something to do with settings on your PVR rather than the TV itself. There should be no need to switch off overscan. Check the display settings and make absolutely sure that it is set to 16:9 widescreen. Never mind if the channel is widescreen or not. Also, as mentioned above, I'd definately take the TV off 'Auto' setting and set it to 16:9 as well. Change it to 4:3 when viewing non widescreen content if it bothers you.

Did you have the PVR plugged in to a TV before this? Was it a 4:3 set?
 

billybug

Standard Member
One question, the other TVs you are comparing to, are they all widescreen? Some broadcasters when transmitting the WS image on cable or freeview crop the top rather than putting out the extra info to the side. Especially with content that was originally recorded in 4:3. e.g. if you watch teletubbies on Cbeebies in widescreen, during the end credits half the credits are missing at the bottom.

that's just how it's broadcast and until everythign is recorded in WS format there probably isn't much you can do about it.

Other than that, you must have an unusually large overscan on that set. The question is whether all PZ70s have it or just yours.

One of the other tv's was widescreen and one was 4:3. But both seem to show the same hieght picture - just the width varied. And the PZ70 was less (height) than both.

Comparing the PZ70 with a standard 4:3, would you expect any difference in what is shown height wise on the screen?
 

billybug

Standard Member
I'm pretty certain this has something to do with settings on your PVR rather than the TV itself. There should be no need to switch off overscan. Check the display settings and make absolutely sure that it is set to 16:9 widescreen. Never mind if the channel is widescreen or not. Also, as mentioned above, I'd definately take the TV off 'Auto' setting and set it to 16:9 as well. Change it to 4:3 when viewing non widescreen content if it bothers you.

Did you have the PVR plugged in to a TV before this? Was it a 4:3 set?

Yes the set was previously a 4:3 - so I will check that the PVR is now set to 16:9.

However, the problem exists with the TV even when not connected to the PVR. It still slightly cuts the top of the screen off.

Its only when connected to the PVR that the _ _ _ _ lines appear.

So the basic consensus of opinion is that I shouldn't have to put overscan to 'OFF' to get a full screen?

Does anybody else set overscan to 'OFF'?
 

Ian Dudley

Active Member
Comparing the PZ70 with a standard 4:3, would you expect any difference in what is shown height wise on the screen?

To be honest, no I wouldn't. I'm reaching for an explanation as something weird is happening on your set.

But I have seen cable channels that when they broadcast old 4:3 footage on a widescreen digital channel, crop at the top and bottom to make the picture 'fit'. I don't really think this is what is happening to you, but it's possible.
 

billybug

Standard Member
Ian

I first noticed it watching...... east enders on BBC 1 i think, and then again on a new programme on ITV - so it was deffinately not noticed on old programmes.

I'll have another look this evening and see if i can work out exactly how much its missing off - and also try and take a couple of fotos.
 

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