auto screen brightness + slider ... makes sense ?

[sethidheeraj06]

It is not a bug in lollipop.. It is a facility provided by google that if u have set brightness to "auto".. And after that u want to dim the light.. Or increase the light .. So u can ..

 

[vijyes Yechuri]

It is adaptive brightness. Slider determines the sensitivity of the brightness in case adaptive brightness is turned on. If you keep the slider on 50%, it will work the same as auto brightness. If it is 30%, then the brightness will be equal to the brightness of the external illumination which is 20% less than current illumination. So, essentially it helps people save power or improve readability by adjusting the sensitivity of brightness according to individual preference. Just keep the slider on 0% and then shine a bright torch at the sensor. You will find that the screen brightness goes to 100% thus vindicating my claims

 

[Karlman Lee]

Aha, i just happen to check this issue recently, after digging into the source code carefully, i found that was designed by google. With Auto Brightness option turned on, when you are moving the slider, you are changing the gamma value instead of changing the screen brightness directly, then the gamma value and the Lux value of ambient light will be used by certain algorithms to calculate the final screen brightness.