Some like the http://www.samsung.com/us/support/owners/product/UN65F7100AFXZA have some pretty recent firmware. ASK SAMSUNG how to find and install the latest as well as resets and settings.
From the manual "Cinema Black
This function is only available on the LED 7050/7100 series, except 75-inch TVs. In Movie mode,
this feature dims the top and bottom areas of the video image to provide a more immersive
So I'd dive back into the manual to find all effects like that.
My Samsung 65 inch F7100 lcd 2 year old TV recently started developing a problem where the picture darkens for a period of time. Interestingly, when I am in picture on the menu, the picture corrects itself but goes back to dark when I exit. I have turned off the energy saving and Eco sensor functions. I have also switched my hdmi cable to my Directv receiver. I did get a new receiver from Directv about a month or so ago. The problem persists. I have the TV in an armoire but always have. I am not sure if it is a bad Directv receiver, a TV problem, or something else. Any insight would be appreciated.