Just to note, there are two main types of Sodium lighting. One is the street light that looks generaly "orange" in colour, and high pressure sodium that looks more "peachy white". The orange sodium has just a single spectra line hence no colour is seen. (look in a carpark at night where this lighting is used and try to see the colours of the cars). The peachy form of sodium has more spectrum and will allow more colour to be seen, but as mentioned by Garry, a low colour temperture is exhibited.