Ambient light sensor that auto-adjusts picture to room lighting?

I found this feature to be annoying as it continually and very noticeably adjusted the brightness for seemingly no apparent reason. The feature appeared to act like it had little to no built-in hysteresis. So far as I can tell, It might have even been reacting to the change in light level caused by its own brightness level changes. I turned it off.

Both LG and Samsung models have this. On most mid-high end LGs you can adjust the maximum and minimum brightness change as well as the sensitivity of the feature, I'm pretty sure Samsungs also offer this adjustability--you might try downloading Samsung owner's manuals from their website to verify.