Makvision Monitor M3129DF-TS discoloration

[Pitou]

Hello,

In my cabinet I have an MakVision monitor along with an ArcadeVGA 3000

When the screen is static, some discoloration start to appear after a couple of mins.

Like in the picture, we can see a blue circle turning into purple on the right side.

It's not burned in. If I turn off the monitor and turn it on back again, it's fine. Again, when waiting a couple of mins on a static screen, it reappears.

For normal usage, when playing mame, it's not an issue.

Could it be dangerous?

Any idea on how to avoid this?

Thank you.

Pitou!

[Rickn]

From what I see, that is what is called "doming". It is caused by a very bright picture which is excessive beam current going through/hitting the shadow mask inside the picture tube. The shadow mask, (I Layman's terms") is a very thin piece of metal inside the picture tube with holes the size of each pixel. The electron beam goes through these and lights the appropriate red/green/blue pixels. When too bright this piece of metal gets hot and bends out of shape, then misaligning the electron beam. So in answer to your question, no not dangerous to you. Yes could be dangerous to the video output transistors of the monitor. If you want to run this screen or others such as a Mame Hockey that might have a mainly white picture, reduce the brightness and contrast.
Hope this helps.
Rick Nieman
Nieman Video Displays

[Pitou]

I'll give it a try and keep you posted of the result.

Thanks very much for the help and the precise explanation. Very appreciated.

Pitou!

[lilshawn]

don't forget you are looking at an old style of display... a tube monitor... not a super bright plasma display. your eyes have been sullied by modern super high definition and big bright displays. You THINK it needs to be as bright as it is.

just turn down the brightness and contrast a bit.

[Pitou]

Applied your suggestion and it works great!

Thank you very much!

Pitou!