Brightness adjustment via mx-tweak does not work (MX-23) [Solved]

[FraterLinux]

I bought an LG ultrawide 26WQ500 monitor. I installed gddccontrol to manage this monitor. This monitor is not supported, but it is possible to use generic configuration. This gddccontrol has monitor brightness setting.

In mx-tweak there is also an option to configure the monitor's brightness. It has a larger adjustment range. However, a few seconds after I adjust the brightness using mx-tweak, the brightness returns to its previous intensity. Even if I click save, the brightness setting is lost.

mx-tweak uses xrandr to configure brightness, is this configuration through hardware or software?
Is there a conflict between gddccontrol and mx-tweak?
What is the path to the mx-tweak configuration file for me to check?

[dolphin_oracle]

the brightness by xrandr is software manipulation of X values.

the hardware brightness control works directly with the backlight control of supported monitors. usually that is just laptops but some desktop monitors seem to also show up.

the software brightness setting is applied directly and also stored under a file name matching the display name under .config/MX-Linux/MX-Tweak/brightness/

that file is sourced by a script at login.

you can check

Code: Select all

xrandr --verbose

to see the brightness level set, and if X is reseting the value or if your monitor is doing something weird.

[FraterLinux]

the brightness by xrandr is software manipulation of X values.

the hardware brightness control works directly with the backlight control of supported monitors. usually that is just laptops but some desktop monitors seem to also show up.

the software brightness setting is applied directly and also stored under a file name matching the display name under .config/MX-Linux/MX-Tweak/brightness/

that file is sourced by a script at login.

you can check

Code: Select all

xrandr --verbose

to see the brightness level set, and if X is reseting the value or if your monitor is doing something weird.

I'll see. My old monitor didn't have brightness adjustment. On this LG monitor I can change the brightness using MX-Tweak, but it returns to the previous brightness after a few seconds.

[FraterLinux]

Two brightness values

$ xrandr --verbose

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HDMI1 connected 2560x1080+0+0 (0x46) normal (normal left inverted right x axis y axis) 600mm x 250mm
	Identifier: 0x42
	Timestamp:  127204
	Subpixel:   unknown
	Gamma:      2.0:4.2:3.4
	Brightness: 0.70
	Clones:     VGA1
	CRTC:       0
	CRTCs:      0 1
	Transform:  1.000000 0.000000 0.000000
	            0.000000 1.000000 0.000000
	            0.000000 0.000000 1.000000
	           filter: 

.config/MX-Linux/MX-Tweak/brightness/HDMI1

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xrandr --output HDMI1 --brightness 0.75 --gamma 0.625:0.37:0.417

[dolphin_oracle]

do you have something running adjusting the gamma? like a redshift type app?

[FraterLinux]

do you have something running adjusting the gamma? like a redshift type app?

Yes. Redshift also changes the brightness?

[dolphin_oracle]

do you have something running adjusting the gamma? like a redshift type app?

Yes. Redshift also changes the brightness?

it changes the gamma anyway.

it might be possible to kill redshift, set the brightness, then restart redshift. I honestly don't know exactly how redshift works, other than the color temp is usually a function of gamma adjustments.

[FraterLinux]

it changes the gamma anyway.

it might be possible to kill redshift, set the brightness, then restart redshift. I honestly don't know exactly how redshift works, other than the color temp is usually a function of gamma adjustments.

I will try to do that.

Before I tried to set the brightness, but also back to the previous level.

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$ xrandr --output HDMI1 --brightness 0.8

[FraterLinux]

It really is the redshift that is changing the intensity of brightness.

I edited the redshift.conf file to make the brightness as I want:

Code: Select all

[redshift]
              temp-day=5000
              temp-night=4000
              brightness-day=0.9
              brightness-night=0.7
              gamma=0.8:0.7:0.8
              adjustment-method=randr

Is there another way for redshift not to interfere with the brightness configuration?

[dolphin_oracle]

not that I can think of. its always tricky to have two utilities muckying around with xrandr settings. especially something like redshift, which presumably adjusts its values every few minutes. with xrandr, you generally have to specify the gamma and the brightness when messing with either, otherwise things get out of sync and unexpected results occur.