Experienced photographers, please help!?

If you're just shooting the lamps themselves, you'll need to zoom in as tight as possible and expose just for the lights - no guarantees, but that *might* show up the difference. However, if you're shooting a broader shot taking in more of the scene, exposing for the lights would mean everything else would be in darkness (I'm assuming the lights are only on at night). Unfortunately, cameras are nowhere near as sensitive or adaptable as the human eye, so there's no real way to expose for both the scene and the lights. You might try shooting a long-exposure at a high f.stop, which *might* result in the light colours burning in, but I don't think you're likely to ever quite get the result you're looking for. Sorry!