Screen Brightness: Sony Vaio

[Marco Antonio]

On Tue, Dec 24, 2013 at 11:50 AM, Rich Shepard <rshepard at appl-ecosys.com> wrote:
>   We have a Sony Vaio running Slackware-14.0/x86_64 and the Fn-F5 button has
> no effect on screen brightness.

Maybe that's the laptop model, sony_laptop module and acpi. I have a
sony vaio model VPCSA4C5E with Slackware 14.0 and works well.

FN + F5
https://dl.dropboxusercontent.com/u/24303764/tmp/sony000.png

XFCE4 brightness plugin (included in Slackware)
https://dl.dropboxusercontent.com/u/24303764/tmp/sony001.png

> I rummaged around in the Settings -> Settings Editor
> -> Display dialog box and changed the screen brightness from the default 12
> to 6. After rebooting there's no difference.
>
>   What am I missing here? A pointer on how to make the screen dimmer will be
> much appreciated.

It is often possible to adjust the backlight by ACPI. When ACPI option
is available, the illumination is controllable using a GUI slider in
the Display/Screen system settings (xfce4-brightness-plugin) or by
simple commands on the CLI:

In rc.local or terminal:

# Set Brightness:
echo 7 > /sys/class/backlight/acpi_video0/brightness
echo 7 > /sys/class/backlight/acpi_video1/brightness

More info: https://wiki.archlinux.org/index.php/Backlight

Marco Antonio