How to change to brightness of an external display on a macbook pro running OSX 10.6

Question

I am using a macbook pro running OSX 10.6 snow leopard.

In System Preferences/Displays/Display, I can change the brightness of the macbook's screen. However, this option is not available for the external monitor.

Is there a way to change the brightness of an external monitor without resorting to changing the settings manually on the monitor itself ?

This happens using both of the mini-displayports adapters (DVI & VGA)

Solution 1

You cannot do this from System Preferences because the video adapters do not have an interface into the brightness controls of the external monitor.

Sorry, but adjusting manually on the monitor is the only way.

Solution 2

Try the preference pane Shades

There is also Dark Adapted, which will change many more aspects of each screen independently, but it is not longer supported (though it works with lion)

Solution 3

In 2020, there are at least two options:

1. Lunar - https://lunar.fyi/
2. MonitorControl - https://formulae.brew.sh/cask/monitorcontrol

My setup is a 2013 MacBook Pro with Mojave, connected to two relatively new ViewSonic VA2359 monitors –– one through Thunderbolt, and the other through HDMI.

Lunar successfully changes the brightness of both flawlessly, though the sync option to adjust the externals based on the setting of the built-in display doesn't seem to be reliable. Still, you can adjust both contrast and brightness from a handy menu bar.

I tried MonitorControl, but while it detected both monitors with separate IDs, changing the brightness on either only affected one.

Solution 4

Use my own fork of Brightness Menulet

It supports auto adjustment based on the ambient light sensor

Link: http://github.com/MuhammadHewedy/BrightnessMenulet

Solution 5

If you are using an Apple external Display you can use Control-F1 and Control-F2

View more solutions

Comments

[gak]

Works great! This should be the reaccepted answer.

[fixer1234]

From @wise_rice: Your fork is awesome and works great with the ambient light sensor! But it does not set the brightness to the lowest or the highest possible values. Only to like 20% and 55%. It would be lovely to have it Set to 1% or even 0% (that is still bright at night on my Dell U2515H) and to 90% at very bright daylight. Can I change that somewhere in the code? (I am not a pro, but I have xCode and all that installed. How do I create an app-build out of your github code with xcode?)

[Dave Everitt]

I have this issue and your reply looks useful, but "drag the menu bar object" - not sure what's meant here?

[Mohammad Banisaeid]

Lunar is awesome. Thanks!

[118218]

I was not expecting that! I thought a specific Monitor was required! MonitorControl is pretty cool (didn't try Lunar). Thanks!