That annoying white dot in the top left of TV1 and TV2 broadcasts

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robjg63

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Topic # 58367 10-Mar-2010 12:15

Hi - I know this got mentioned before, but I have a Panasonic G10 plasma - great picture and everything - very pleased with it.

I watch Freeview HD with the inbuilt tuner.

TV1 and TV2 have this really annoying fully illuminated few pixels in the top left corner of the screen - it just looks like a really white dot at the top left of the screen (I dont think this applies to TVNZ6/7). Doesnt matter if the program is widescreen or 4:3 - its still there. All the other channels are fine. It really annoys me.

There is an 'overscan' function on the TV which (when activated) gets rid of it - this effectively chops some of the border of the broadcast picture then scales the picture up to fit the screen. The trouble is - this actually removes quite a bit of the picture - not just a couple of pixels.

My Samsung LCD and Zinwell freeview box dont show this annoying bright dot.

Im presuming TVNZ broadcast this on purpose and maybe some other TVs just trim it off? Why do they broadcast it?

If its a problem only on the Panasonic Tvs then can it be 'cured' without the overscan setting?

Nothing is impossible for the man who doesn't have to do it himself - A. H. Weiler

magu

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Reply # 305921 10-Mar-2010 12:35

Thank God I'm not the only one seeing things. ;)

It puzzled me for a long time until I decided to ignore it.

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sbiddle

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Reply # 305998 10-Mar-2010 16:19

It's just one of those annoying things. TV broadcasts were typically designed to be overscanned, on a CRT TV it extended to the edges of the tube and you normally had a surround which chopped off a small % of the picture.

With newer flat screen TV's this is isn't always the case so any signalling that's in the picture sometimes shows, on my PVR it's also common to occasionally see lines across the top of the pictures on some old content.

bazzer

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Reply # 306005 10-Mar-2010 16:33

You wouldn't want overscan on a Full HD screen IMO, since there should/could be a 1:1 mapping (maybe you could for 720p but even then...). A better solution would be cropping and adding a border of a few pixels to mask this (i.e. "paint over" the offending pixels in black, say). You'd not really notice a couple of black lines across the top I wouldn't think and it'd maintain the integrity of the remaining pixels.

sbiddle

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Reply # 306006 10-Mar-2010 16:39

You could always get a vivid and paint out the pixel! :-)

robjg63

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Reply # 306014 10-Mar-2010 16:57

sbiddle: You could always get a vivid and paint out the pixel! :-)

Perhaps I could paint it blue and always hope that the sky will be up in that part of the screen!

I emailed Freeview - I am not really expecting a reply.

My guess was perhaps its something to do with TVNZs old tape based program delivery system on their 'HD' feed - Fingers crossed they might get their gear updated one day - though with talk of budget cutbacks etc I am half expecting they will return to analogue black and white broadcast.

Nothing is impossible for the man who doesn't have to do it himself - A. H. Weiler

rvangelder

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Reply # 306024 10-Mar-2010 17:49

robjg63: though with talk of budget cutbacks etc I am half expecting they will return to analogue black and white broadcast.

bring back the goodnight kiwi

dasimpsonsrule

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Reply # 306045 10-Mar-2010 19:09

I noticed that too. A white one in the top left hand corner, and a red and a green one in the bottom right

robjg63

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Reply # 306259 11-Mar-2010 13:18

Well I did get a response from Freeview - In its entirety...

"Overscan should be turned on for Freeview NZ broadcasts."

Perhaps the overscan in the Panasonic TVs is somewhat aggressive - it seems to trim about a couple of cm form around the edge of the picture. All it needs are several pixels. But I guess any overscan means that the picture willed be scaled up - which I imagine is not entirely ideal - Guess I will just leave overscan turned off and try not to notice that bright spot at the top of the screen.

Nothing is impossible for the man who doesn't have to do it himself - A. H. Weiler

magu

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Reply # 306260 11-Mar-2010 13:23

Apparently there is a way to change the amount of overscan through a Service Menu on the Panasonic plasmas.

Googling around returned this: http://www.keohi.com/keohihdtv/brandspecific/panasonic/panasonic_plasma_servicemenu.html

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dacraka

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Reply # 306271 11-Mar-2010 14:29

sbiddle: You could always get a vivid and paint out the pixel! :-)

Haha, that comment cracked me up :)
Would be annoying for the other channels :P