I'm sorry if this is a dumb question. (I feel like I know a decent amount about my MBP and about a/v matters, so, I feel a bit dumb for not knowing the answer to this.) I have an external monitor (Samsung 2223w) monitor connected to my MBP via DVI. The MBP is shut. Is there a way that I can reduce the brightness of the external monitor quickly with software? Of course, I can manually reduce brightness by clicking the buttons on the side of the monitor and navigating through the menus. But is there a way that I can set a keystroke to do the same?