Screen brightness

Ever since I upgraded to A9 I can’t take the brightness of th screen as low as before. It seems there’s this file /sys/devices/mdp.0/qcom,mdss_fb_primary.171/leds/lcd-backlight/brightness that controls the minimum value (or is it a multiplier?) that one can set. Of course, you can’t change the contents of that value unless you’re root. For more details, see here:

Can someone prod the developers and ask them to change this value to what Android7 had?

I recommend you open a ticket in the issue tracker:

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It neither controls the minimum value nor is a multiplier. It controls the actual value of the brightness, and is dynamically updated each time the brightness changes. The minimum value is defined by the system through the brightness slider, not by this file (nor another file in the same location).
If you read again the thread you linked, you will see you can indeed modify this value when rooted, but you will need to do so each time you want to go under the minimum value of 10 imposed by the system.

Did/do you use battery saver on permanently? Because under android 7, battery saver reduced the minimum value from 10 to 7 (lower brightness), which isn’t the case in android 9 anymore (I just tested it), but the minimum value didn’t change.

You may want to add these details in your issue and link to this thread.

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No, only when batt dropped below 15%.

You mean, under normal conditions (t.i., not under battery saver).

Let me see if I can get it right. A7 allowed to set the brightness from 10-???, except under battery saver, when it let you go 7-???. Now A9 only lets you set 10-???, battery saver or not.

I don’t know, all I can say it’s that now I have to squint or slant the screen at night. Maybe some other part of the stack is also playing with the values sent to the HW. A9’s adaptative brightness says it learns from your input, but I find it always brighter than the one from A7. I might even be a little photophobic, I don’t know.

Let me be more clear here. I’m talking about from (civil) twilight to total darkness, assuming no artificial light in the room.



Hmm, you’re using adaptive brightness. But (just to be sure), you did try to reduce the brightness slider to minimum, and it still too bright?

not anymore, was always too bright.

yes, in dark situations it’s always one position above the minimum, I slide it all the way down and it’s still too bright. I will check again later (morning here now), but I think there’s even not much difference between those two.

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I have a workaround: I installed Dimmer from F-Droid and use it in very low light conditions. The UI confused me at first, but just use the || (pause) / |> (play) button to turn it off/on; X closes the app and removes it from the notification dropdown, so it’s not so easy to reach again later.

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