I have an iMac 2012 with core i5 but the brightness control doesn't work. The brightness works when the screen saver is activated but deosn't work with the F1 and F2 buttons. Now i'm working with an Ubuntu 12.04, How can i solve this problem?
Because that feature is a hardware related feature you can map the keys for brightness UP and DOWN. I do not remember of the right article right now, but search for mapping keys, and you can make your keys change brightness. Probably you will have to edit a file. There is already a post about that. Sorry for no solution right now, but it is possible to solve it. ;)