You've likely noticed that most city street lights aren't quite pure white. Some emit a warm, orange colour, while others are cold and green. When you're shooting photos that can be an annoyance if you don't want the colours to distract from your scene, but the types of light used are so common that you can easily compensate for them.
Photo by Patrick Tomasso via Unsplash.
Over on PetaPixel, photographer Alex Zhu recently took a look at three of the most common types of street lights and what you can do in post-processing to achieve better white balance. When an entire street is lined with a single type, you can adjust the colour temperature and tint on your photo so that it looks like all the street lights are pure white. Keep in mind that doesn't necessarily make your photo better — and in some circumstances, makes the scene look cold. But knowing the three types of light that you'll frequently encounter will give you leg up when editing your photos. For example, orange-ish lights are likely high pressure sodium lights that you can easily adjust for:
Reducing the colour temperature drastically, by using colour temperatures in the low 2000s, makes photos look more balanced and pleasing, while still retaining the familiar and cosy feeling of warmth the amber glow provides.
Zhu also notes that in real world circumstances, it's entirely common that there will be multiple types of light in a shot so you'll rarely encounter the perfect circumstances in which you can compensate for every single light. Moreover, there's an art to this; there is no such thing as perfect white balance. You should adjust the scene in a way that supports whatever you want to evoke. Read Zhu's article to learn about the other types of common street light, including metal halide and mercury vapour lights.