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Ask HN: Why does my monitor flicker when it shows a certain static pattern?

4 points by peterisza ↗ HN
When I load a certain static image (basically a blueish or greenish pixel checkerboard), my monitor starts flickering heavily.

Test images: http://engineerjs.com/wtf1.png http://engineerjs.com/wtf2.png. Make sure to download them and use actual pixel-correct zoom (does not work in the browser).

Videos: https://photos.app.goo.gl/rMRuUEe7kHorpwtf6, https://photos.app.goo.gl/NT3LwxCoorYYT2cc7.

What could be going on here? Is the monitor faulty? I bought it 4 days ago. It is supposed to be "FlickerFree" according to the manufacturer (https://www.philips.hu/c-p/276E8VJSB_00/4k-ultra-hd-lcd-monitor).

4 comments

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compressedgas
The thing to blame is the enhancement filter. It is meta-stablity in this filter that is causing the flickering. It is doing the same as what happens when a visual cortex processes an optical illusion. It can not resolve it to one steady state.

Look in the monitor menu for the setting that turns the following off:

   Picture enhancement: SmartImage game
peterisza
Thank you for the comment. There is no such setting. I have been playing with the settings, but none of them seems to affect the flickering so far. I am going to return this monitor.

On the other hand, I really don't get how the enhancement filter is not stable. It is just a convolution, right? There is no temporal element to it, is there? So if all the input frames are the same, all the output frames should also be the same, I guess.

Bottomline: cheap stuff is almost always more expensive than expensive stuff.

compressedgas
It's not in the menu because they have it set up to be toggled by the left directional button. See the manual https://images-na.ssl-images-amazon.com/images/I/B15IIYjIA0S...
peterisza
I see. Now I tried all the settings in that left button menu and the flickering does not go away (it is the same when SmartImage Game is off). It is the same with my desktop computer and my MacBook Pro as well.

I hope the store will take the monitor back. Otherwise, I will make a "will it blend"-style video with it or similar.