Giz Explains: BrightnessJohn Herrman9/28/10 4:00pm961EditPromoteGo to permalinkYour smartphone's screen: 500 nits. Your laptop's: 400. Your living room projector bulb: 1700 lumens. Your mini Maglite's: 16. To gadget makers, brightness is a numerical marketing weapon, wielded often and without grace. To us, it's just another spec. No more!