Photography is all about light, and street photography is by definition outdoors (arguably with some exceptions), so photography outdoors at night is a particular challenge, both technically and visually. Personally I am not looking for the in-your-face style made notorious by Bruce Gilden, so flash for me is out. That leaves an intriguing hunt for existing artificial light sources in a variety of forms, and it is this pursuit of “found” light sources which interests me.
The obvious starting point is normal street-lighting, but this does not generally yield interesting results as a) it comes from above and is therefore not good at illuminating faces; b) it is often a strange colour, such as sodium lighting (this can be used as an effect but it tends to be rather drab); and c) it is by design rather even in its modern incarnations and therefore does not produce very interesting effects. This version of the now-clichéd person in a striped shirt on a zebra crossing deliberately uses strong colouration of the street lights to produce something different from the usual black and white effect.
I always shoot my night images in colour: I find that the exaggerated colours of city lights give a special quality to the images which would be missing in black and white. Of course, monochrome could be used to create a moody, film-noir image, but I like to try and capture the vibrancy of the city at night. Indeed, I use a Kodachrome film simulation (Exposure X) to emphasise the bright colours and in particular the reds.
Of course, dim lighting can be used to create a mood in colour as well, such as this slightly sleazy image of a bar featuring drag shows in Key West.

“Night Spot”
An advantage of taking street photographs at night is the anonymity that darkness brings. It is usually desirable not to be noticed by one’s subject in order to to capture a candid view, but when photographing the sleazier areas of town it can be even more important in order to avoid potentially difficult situations. It is important to be open though – not to hide the camera or look shifty – but it can be easier to blend into the background at night. It helps to blend in to the background if you wear dark clothes, but it is important to stay safe, both from traffic and from any unsavoury characters lurking in the shadows. Always know where you are and how to get back quickly to a well-lit area where there are people about.
It is useful in any kind of street photography to have unobtrusive equipment for and it is better at night if your camera is not too shiny! You can cover up any bright parts with black tape. Low light situations introduce additional technical issues: good noise performance at high ISO settings is desirable, and wider apertures are usually desirable to keep the shutter speed adequate for hand-held shots. This in turn places more emphasis on good technique, in particular focussing and stability. (See panel – Equipment and Technique).
This image of a Soho bouncer was taken through an open doorway and was certainly a situation where a subtle approach was required.

“Bouncer”
Shooting through windows into a lit interior can provide a good light source while retaining a street “feel”. It can be either a dimly lit interior such as a nightclub, as with “Bouncer”, or a brighter interior such as a restaurant. The door or window can also provide a natural frame for the image. In this Italian restaurant I was struck by the triangle of people formed by the waiter and the two customers, with an expression resignation on the face the waiter and of boredom on the face of the diner on the left as they wait for the other customer to choose from the menu.

“It’s going to be a long night”
Sometimes the light itself can be part of the subject. I particularly like finding islands of light in a dark street, such as food stalls (“Superdog” above) and News Stands. The vibrant colours used to attract the customers can create a strong image, and the pool of light also helps illuminate the faces of the vendor and the customers. Alternatively the signs and displays of a shop or restaurant can provide a subject in themselves.

“Ed’s”
Other ways of picking out faces from the darkness include the light from mobile phone and tablet screens and the light from shop and restaurant windows, in particular the kind of illuminated menus you sometimes see outside restaurants. This one is in London’s Soho. The good thing about a menu is that people stop and look at it, and you can catch some interesting expressions as they evaluate the fare on offer.

“Sid”
In warmer climes, late-night shops often display their wares outside and again people pause to assess the goods on display. Food stalls are good because customers will pick items up and examine them. The vendors themselves can also make good subjects. This shopkeeper taking a cigarette break seems oblivious to the healthy message of his shop.

“Viva la vie”
Looking for ways to illuminate faces is not the only possibility. Shop windows for example provide an ideal opportunity to capture silhouettes. As with all street photography, it can be rewarding to pick a spot and wait for a passer-by who complements the particular shop window.

“Know Your Apples”
Advances in sensor technology are making photography possible in much lower light levels than ever before and opening up the night-time as a new stage for street photography. Make the most of it!
Equipment and technique
I use a Fuji X-T1 which is small and unobtrusive but which has a fairly large APS-C sensor for good low-light performance. Autofocus can be unreliable at night and the lower depth of field associated with larger apertures places more importance on accurate focussing. Shutter speeds will inevitably be lower and steady hands will be required to avoid camera shake. I usually prefer manual focus using a zone technique but you need a lens with a good focus scale which many modern lenses do not have. I use an old Leica lens via an adaptor: it is small and light with a long throw on the focussing movement and a good depth of field scale, making it easy to pre-set a focus zone.
Don’t be afraid to use a high ISO – a slightly noisy image which is in focus is better than an out-of-focus image. If you are able to choose a camera with good performance at high ISO settings that will help.
Dynamic range can be a challenge, so you usually need to decide whether you want to capture the shadows or the lights: that will depend on the subject you have chosen. Exposure bracketing can be used with static subjects, but if you are trying to capture a moment it is better to decide on your exposure in advance. Using manual exposure can help to avoid wildly varying exposures as you reframe. Each time you move to a new area, take a few test shots and look at the histogram if possible. Then set your exposure for the part of the lighting range you want to capture.