So I have white font with a drop shadow in 3d and am attempting to have a red light which moves across the letters (like an alarm light). However, when applying the light, all of my colors turn black. I have all shadows switched off on the light and the words, has anyone had a similar problem?
Just making sure I understand: You have a text layer set to 3D, and it's fine until you add your red light, correct? If your red light is the only light in your scene, then any time the red light is not pointing at your layer (you say it's sweeping across) the layer will be in complete darkness. Try adding an ambient light to the scene and see if your text comes back.