Side-margin distortion when in 4:3 mode


Well-known Member

I've been playing about with the geometry on my Panny 36PL32 for a while, and have finally managed to get the geometry issues I had with it (straight lines bending at the edges of the screen, image not centred and over-stretched and most annoying wobbly side margins when in 14:9 and 4:3 modes) sorted. The side margins are now nice and straight, however when something flashing and bright comes on to the screen (think ITV-F1's opening credits or an old Top of the Pops with the overhead lights flashing and swinging away) the picture in 4:3 or 14:9 flexes and pushes into the black margins (as in it distorts into them, turning the straight border-definition into a dancing wavy line). As soon as the bright image has gone the nice straight borders are back. Does anyone have any idea what could be causing it (and how to fix it!!!)?

Many thanks,



Distinguished Member
As chedmaster says, it's something that virtually all CRT sets suffer from. It's caused by variations in the set's internal power supply regulation depending on picture brightness and beam current. The effect does vary from model to model but very few, apart from expensive studio monitors, are near perfect.


Well-known Member
Thanks! I was worried I'd messed something up when playing in the service menu! A weight off my mind! :clap:


Is this reason enough to not buy widescreen CRT and go LCD or Plasma I wonder, or would a Sony Wega top notch CRT be ok and free of this ?
I am considering a widescreen as my next TV, being a 4:3 CRT Sony 28inch currently.
Is there a test DVD to put a TV in a shop through its paces I wonder ?



Staff member
Merlin said:
...would a Sony Wega top notch CRT be ok and free of this...
Nope. No consumer CRT TV will ever be free of it; would cost too much to manufacture. Some Loewe models have it fairly welll minimised. The only assured way to perfect geometry is a direct view flat panel (LCD or Plasma).

Sarah Nya

I've got a Loewe Articos and I don't see any problems with it at all, especially when I compare it with my old Toshiba widescreen that thing used to drive me nuts I could never get it straight!

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