Dark picture the screen dims for better blacks, bright daytime outside the tv/monitor contrast gets pumped up.
Best to turn it off and calibrate it, then it will be even thought out.
I purchased a i-inc monitor with a 15000 dynamic contrast w/2hdmi connectors, which is connected to my pc. Anyways I thought that it would brighten out the blacks (shaded areas) while i watch movies on my pc right? Instead it fades the entire screen when the screen is in a dim low light situation. Making it hard to see anything. When the lighting is back in the movie only then is the level balanced. Is this how dynamic contrast is suppose to work or is this a problem with my monitor?

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