Brightness Settings Don't Work

See https://wiki.ubuntu.com/LaptopTestingTeam/HotkeyResearch

I don't think you understand... I said the function keys *do* work.

Setting this to Gnome-Power-Manager package,

This is more likely a 'hal' or kernel issue:

  /usr/share/hal/scripts/hal-system-lcd-set-brightness

Currently has the following code for Sonys:

  elif [ "$HAL_PROP_LAPTOP_PANEL_ACCESS_METHOD" = "sony" ]; then
        # echo "{1..8}" > /proc/acpi/sony/brightness
        # http://popies.net/sonypi/2.6-sony_acpi4.patch
        echo "$((value + 1))" > $HAL_PROP_LINUX_ACPI_PATH

Does this work on your laptop. Could you also please include the DMI decode data for your laptop as detailed on the HotkeyResearch page above so that we can identify your laptop.

I'm not sure quite what you mean by does it work. Please clarify.

DMI data:

Sony Corporation
VGN-S4XP_B
J000VXDY

Can confirm the same issue with my vaio S1XP.

DMI decode data:
Sony Corporation
VGN-S1XP(IT)
J0009F44

I guess my bug report:
https://bugs.launchpad.net/ubuntu/+source/gnome-power-manager/+bug/92478
and this one:
https://bugs.launchpad.net/ubuntu/+bug/103890
are duplicates.

same problem on vgn-fe31z

here the problem is solved using smartdimmer (only with nvidia)
on feisty change /usr/lib/hal/scripts/hal-system-lcd-set-brightness

elif [ "$HAL_PROP_LAPTOP_PANEL_ACCESS_METHOD" = "sony" ]; then
        # echo "{1..8}" > /proc/acpi/sony/brightness
        # http://popies.net/sonypi/2.6-sony_acpi4.patch
        echo "$((value + 1))" > $HAL_PROP_LINUX_ACPI_PATH

by

elif [ "$HAL_PROP_LAPTOP_PANEL_ACCESS_METHOD" = "sony" ]; then
        # echo "{1..8}" > /proc/acpi/sony/brightness
        # http://popies.net/sonypi/2.6-sony_acpi4.patch
        smartdimmer -s"$(($value * 3))"

and /usr/lib/hal/scripts/hal-system-lcd-get-brightness

elif [ "$HAL_PROP_LAPTOP_PANEL_ACCESS_METHOD" = "sony" ]; then
 # cat /proc/acpi/sony/brightness
 # 7
 value="`cat $HAL_PROP_LINUX_ACPI_PATH`"
 value=$(($value-1))

by

elif [ "$HAL_PROP_LAPTOP_PANEL_ACCESS_METHOD" = "sony" ]; then
 # cat /proc/acpi/sony/brightness
 # 7
        value="`smartdimmer -g`"
 value=$(($value/3))

[Expired for hal (Ubuntu) because there has been no activity for 60 days.]

Try typing the following command in a terminal:

xgamma -gamma 0.75

If that doesn't work you need to install xgamma from the repos.

I have posted my own solution here on setting it up:

http://ubuntuforums.org/showthread.php?p=4168042#post4168042