[RESOLVED] Even lower screen brightness?

I use my laptop as a TV at night when I go to sleep, but the lowest brightness is still too bright for my wife who is trying to sleep.
Is there a way to get even lower brightness than the lowest option currently available?

I am on Fedora 37, but I can entertain switching to something else if it makes it easier.

2 Likes

I had the same needs and was previously using the script in this thread to reduces screen brightness to minimum.

Recently I discovered and started using Light. I set some shortcuts using the alt key with the screen brightness keys which works well for me. Pictured is my minimum brightness shortcut and brightness step up shortcut.


An increase brightness value of 0.18 gives me 4 steps between absolute minimum (0.1 in Light) and minimum brightness using keyboard controls (1.0 in Light).

You can also turn the backlight off completely if you keep stepping the brightness down or set it to zero.

6 Likes

It’s wild as I pride myself on knowing of programs like this, but this one is a new discovery - I like it! Bookmarked. :slight_smile:

2 Likes

I am using the settings below in i3 and sway config. The lowest brightness is no problem.

...
# Brightness size 
set $brightness_size 2
...
# Framework Laptop F7: XF86MonBrightnessDown
# The --min-value option is important to prevent the complete darkness.
bindsym XF86MonBrightnessDown exec "brightnessctl --device intel_backlight --min-value=1 set $brightness_size%-"
# Framework Laptop F8: XF86MonBrightnessUp
bindsym XF86MonBrightnessUp exec "brightnessctl --device intel_backlight set $brightness_size%+"
...
3 Likes

Nicely done!

1 Like

I had the issue too. The ubuntu mate desktop goes by 5% increment. So I needed to go below 1%
Bit now I have a mate screen to correct the mirror effect and it remove some light…solving both problems. We definitely need a mate screen option :grin:

As a note, I am using a matte screen protector. You can see Matte screen protector for details.

2 Likes

I installed light and was not able to get it to lower the brightness lower than the default GUI tools. At the lowest setting in the GUI tools, light reported brightness at 0.78. Lowering it to 0.01 did not have any noticeable effect.

@Matt_Hartley could we reopen this ticket or test that the solution works on AMD boards? I am not able to get any lower brightness using light on my AMD 7640.

These are the available devices on my system:

$ light -L
Listing device targets:
	sysfs/backlight/amdgpu_bl1
	sysfs/backlight/auto
	sysfs/leds/input2::numlock
	sysfs/leds/input2::capslock
	sysfs/leds/input2::scrolllock
	util/test/dryrun

I see that there may be some issues around setting backlighting on amdgpu_bl1 here: AMDGPU Backlight issues / Laptop Issues / Arch Linux Forums

Test brightness on a tested/supported distro. Live usb works. Make sure it’s just the distro. We use it just fine on Ubuntu 22.04 and Fedora 39.

Also I assume you’re on 3.03 bios update?

On Arch with 6.6.1-arch1-1 both light and brightnessctl reach the same value of 0 and brightness (darkness :thinking:) for me (AMD 7640U).

brightnessctl outputs:

Device 'amdgpu_bl1' of class 'backlight':
	Current brightness: 0 (0%)
	Max brightness: 255

My keybinding in sway is as follows:

bindsym XF86MonBrightnessDown exec brightnessctl set 5%-
bindsym XF86MonBrightnessUp exec brightnessctl set +5%

Test brightness on a tested/supported distro. Live usb works. Make sure it’s just the distro. We use it just fine on Ubuntu 22.04 and Fedora 39.

Also I assume you’re on 3.03 bios update?

I am on BIOS 3.03 and using Fedora 39.

Using GUI tools (and the hardware buttons) I am able to control the brightness from 100 down to 0.78.

Using light I am able to set brightness from 100 down to 0.00, but there is no visual difference between 0.00 and 0.78.

At 0.00, I expect the backlight to be off, but it is still on (and still too bright).

@Matt_Hartley, OP reports that they are able to turn the backlight off completely using light-- are you able to reproduce this?

Don’t have the cycles to install light and test against this today on Fedora. However, the moment we deviate from a default config, all sorts of new challenges present themselves in trying to replicate. Especially true outside of vetted/supported distros.

Light is not tested whatsoever and is a community support application. Using brightnessctl is fine and would be expected to work correctly, but op is using Arch. So hard to say.

They need to test against Fedora.

I’m not OP, just sharing my experience under Arch. light and brightnessctl both work fine and are able to set the same brightness values with matching results in light output. There might be differences between AMD and Intel in backlight behaviour.
I remember my Intel Dell XPS being able to turn it off completely as well just by setting brightness to 0 regardless of used tool. It was relatively big step from lowest to off on that machine, so probably not helpful for @gaben.

Appreciate you chiming in with your experiences, always good to get another perspective.

11th gen and AMD Ryzen 7040 Series configs both “work out of the box” with the slider in Fedora and Ubuntu, plus on the keyboard. 12th and 13th gen require module_blacklist=hid_sensor_hub as described in the guides.

Same here.
AMD 7640 on linux mint, but the minimum brightness at 0% is also way to bright for my convenience in the evening.
Using it in complete darkness (such as when camping, as I quite often do) will be impossible.

Using redshift helps a bit, but having a wider range of the brightness itself would be great!

1 Like

Appreciate the feedback, using Redshift may be the best option in this situation.

Would also love to see the ability to modify the minimum brightness. Too bright in dark situations. Native support would be wonderful.

5 Likes

Appreciate the feedback, will pass this along.

2 Likes

I’ve been having this same issue (I’m on a 7840U, with Linux kernel 6.1.71, NixOS 23.11)

I’m still running X11 as Wayland still has some papercuts for me so to get the screen to turn off completely I’ve found that xset dpms force off works for me, typing or moving mouse causes it to turn back on.
For wayland this thread has suggestions involving vbetool and setterm for solutions not involving X but I’ve not had any luck with these.

Some other laptops I’ve owned have had dedicated backlight off function keys other have the minimum brightness when you cycle through the brightness up/down function keys be completely off. I don’t have a strong preference for either of these as long as there is an easy way to set the screen/backlight to completely off, and the steps are sufficiently granular that I can achieve a comfortable brightness in pitch dark conditions.

I’m not sure exactly where is the stack the min/max brightness and step increments are set but if this is something that can be resolved in an OS independent fashion in the framework firmware this would be something the I’d really like to see in future revisions as it’s a big quality of life thing for me.

Consolidating some other posts on this topic under this thread so that there are cross links when people land on one of these in search:

2 Likes