Dynamic Contrast Blues
I have a 40-inch Mitsubishi LT-40164 LED-edgelit LCD TV that I really love but for one thingthe screen darkens dramatically during dark scenes and even during credits when there may only be one or two lines of text on the screen. I have tried tweaking dozens of settings, including full backlight and brightness, but to no avail. Is this normal for LED TVs?
You're describing a dynamic-contrast feature that is very common for all types of modern flat panels, and your experience is why I generally turn this feature off. In the Mitsubishi 164 series of LCD TVs, it's called DeepField Imager, and the control is located in the Picture menu. It's the only setting I can find that has anything to do with what you're seeing. Have you tried turning it off? This should fix the problem, though the perceived black level will probably increase as well.
Assuming that works, I would then reset the basic picture controls using a setup Blu-ray such as High-Definition Benchmark, Digital Video Essentials: HD Basics, or Disney's Wow; if you don't have a Blu-ray player, use the DVD version of Wow or HDTV Calibration Wizard. Start by setting the Picture Mode to Natural (this set has no Movie or Cinema mode) and make sure the Color Temp is set to Low. Then set the Brightness, Contrast, Color, Tint, and Sharpness controls according to the setup disc's instructions. Finally, reduce the Backlight control to the lowest setting you can tolerate so the blacks are as deep as possible without DeepField Imager.
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