Set screen brightness battery/power

[VPrime]

Hey, I am just wondering if there is a way to have a brightness preset for when the macbook is plugged into the wall and running on battery?
Eg. When plugged in I want 100% prightness, but when running off battery it automatically lowers the brightness.

Right now I manually lower it and some times forget.. especially times when I need that extra bit of battery power

 

[GfulDedFan]

The only automatic display dimming process that I know about is in System Preferences/Energy Saver and use the dropdown for Savings for: at the top and mark it for Battery. Next hit the Options button about 1/3 down the page and click the first box that says Slightly dim the display when using this power source -GDF