add
http://pastebin.com/hjmc6HxF
to your init.sqf, however it comes with a few warnings.
1. If you players have NVGs this will break them when they have their RPG in their hands.
2. setAperture persists from mission to mission, hence the mission event handlers. There may be some way for this to not get executed, in which case they could be stuck in the dark.