Manual brightness act like auto.

Vasile CorneliuVasile Corneliu Level 2
edited August 2021 in ZenFone 8

Same story, I'm on manual brightness, now on 100%, 90Hz refresh rate and tilting, watching phone, scrolling Web on different angles dim my brightness auto. Yeah, now I use screenrec and did it 4 times already. I'll link video.


  • Hi. I noticed my display dim the brightness a bit when I set it up to maximum when I change the viewing angle. Latest firmware, manual setup, auto, 90 - 120 Hz, doesn't matter. Anyone? What's the point of lowering brightness if I set it up on max on manual?

  • CH_ASUSCH_ASUS admin
    edited June 2021

    The device isnt changing brightness if you are turning your head or tilting the device. Off-axis brightness will not be the same as straight ahead.

    The maximum brightness will also be achieved in Auto, under HBM scenarios (bright sunlight).

    There's nothing wrong at all with the description so far, from what I can tell.

  • I'll read and watch something in sunlight for example on a 90 degree with smart screen on and brightness set to 100% on maximum. Then maybe I switch head to look something different and lower some 10-15 degree the phone which decrease after some seconds my brightness. Its like preparing for stand by... If I watch again the screen on 90 degree the brightness comes back to 100%. I set up the turn off screen on 1 min. So... Can Zenfone maintain 100% brightness for a bit longer than some seconds when not looking at the phone?

  • I don't think it's a bug, but seems Zenfone doesn't consider maximum brightness neccesary when someone isn't looking at the phone for saving battery. For me instead manual is manual and should ABSOLUTELY override AUTO mode. 😁

  • CH_ASUSCH_ASUS admin
    edited June 2021

    Set display timer to 5min (or 10min)?

    Conversely, does the same thing happen "indoor" in the same scenario.


    The display sleep timer (15sec, 30sec, 1min, etc) will dictate when the display starts dimming.

    It will start dimming ~7-10 seconds before the "sleep timer" is up.

    Edit2, some clarifications:

    Manual brightness (adaptive brightness OFF) does not affect the display sleep mechanism. It does not mean the display wont turn itself off until power key is pressed.

    Manual brightness does not mean manual display off.

    The display sleep timer is just that. It goes on a cycle, 1min in your example, and prior to that 1min is up, display will start dimming itself first step - and then turning itself off.

    Smart screen on, as the description, will also not continously scan for a face infront of the device, but will also do so periodically (more often than once a minute though).

    Can there be instances where you "dipped in with your head very briefly" but the mechanism wasnt actively detecting ? Yes , I suppose that can happen.

    And if your display sleep timer is also short at that, then the above scenario as you described can happen.

  • I also have a similar problem. Adaptive brightness is switched off but the screen brightness changes when the lighting of the room changes or the sun goes behind the clouds or comes out of the clouds. It works just like adaptive brightness but it is switched off. Is there another setting for this somewhere? I want full manual override of brightness setting not a choice between adaptive and a little less adaptive. Maybe a setting in the developer options?

  • Yeah... Didn't capture the screen dim wtf...

  • Finally... Means I'm not crazy... Ty mate 😁👍

  • Lighting in a room changing should not affect screen brightness - when Adaptive Brightness is set to 'Off'.

    When Brightness is set to "Max" in 'manual brightness' (Adaptive Brightness off) and the phone is under strong sunlight, HBM (high brightness mode) will still trigger (just like in Auto) - to boost the display for "maximum sunlight viewing ability" under sunlight.

    This HBM mode will not trigger in "max brightness" in manual, if not under a very bright sunlight environment (a normal indoor lighting should not be bright enough to trigger this, either in manual or auto mode).

    1. if you are viewing the display at different angles - it does affect the brightness you see. This is not unusual for all displays.
    2. At manual 100%, HBM can activate under very high brightness conditions (sunlight) - triggering the HBM brightness mode (up to 800 nits).
    3. If you are on Auto refresh, refresh rate can change, which can affect the gamma curve, which would seem like a brightness change but it mainly a gamma curve change.

    I will merge this thread with your other one also concerning manual brightness.

  • Thank you for your reply. The "High Brightness Mode" explains the behaviour. Is there any way to manually switch HBM on or off or is it only auto with sunlight?

This discussion has been closed.