Question about Vizio M420VT 42 in. LCD HDTV

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Screen darkens randomly as if ambient light sensor were kicking in. I have the ambient light sensor turned off!

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The Ambient Light Sensor isn't perfect, but if you're having the same problem I had, it's not an issue with the Ambient Light Sensor. Rather, your solution will be turning DCR (Dynamic Contrast Ratio) to Off.
Go to the PICTURE menu and choose Picture Mode. You can turn off DCR in one of two ways: Choose "Custom" and set it manually, or choose "Movie" or "Game" for your picture mode. (The "Movie" and "Game" default settings include DCR=off, whereas "Home" will include DCR=on.)
Keep in mind that you will need to make these changes for each input (HDMI, Comp, AV, DTV/TV). Also, if you continue to have trouble you can also try playing with Adaptive Luma under the "Custom" settings.

Posted on Jan 24, 2011


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