I'm the marketing manager for a sign company in Ohio. Part of my job requires that I take photos of completed signs. Some sign photos that have lighter colors featured in them come out washed out. I'm sure this comes from leaving the aperture open for a long period of time in order to get a good shot at night without upping the ISO. I've been fixing the problem spots in photoshop but i'd like to know if there is a way to take the pictures without this problem ever occuring. If anyone has any insight I'd appreicate it. Tips on general night time photography would also be appreciated.