I have lived in a city ever since I was a little kid. Thus, the sights of skyscrapers, busy highways and so on are very common to me, by day and by night. Although I have fallen in love with nature over the years and found myself hiking and trekking in totally non-urban places, I have always had a place in my heart for the city.
As a photographer, it is very much the same; I love taking photos of nature and yet, I also love to find good spots in the big city to show through my pictures how beautiful it is.
The combination of slow shutter speed and city lights allows for a great variety of options. If used wisely, the long exposure contributes to the beautiful effect of moving traffic as well as capturing the steady lights. Combined with seascapes, the results can be even more impressive.
In this article, I will try to impart some guidelines for capturing cityscape images. Location, exposure and timing are the key points for a winning picture. This is not a generic long-exposure tutorial, which is common and can easily be found online. I will be more specific about cityscapes at twilight.
First of all, you need a very sturdy tripod. Whenever we talk about slow shutter speeds, it is imperative to mention a good and sturdy tripod. Needless to say that you should be on location early and allow plenty of time for your compositions; rushing your preparation will not work. As for the ISO, always use the camera’s native lowest ISO available for best results in image quality. In some cameras this is 100, in others 200.
Plan your frame. Choose your location wisely. Your point of view and perspective are crucial for a good composition. If possible, use leading lines which will subsequently be discussed in more detail.
When I say ‘twilight’ I mean evening twilight. This time of the day is magical. The sun has already set, but leftover light still lingers in the sky, which results in the familiar dark blue colour we often see in pictures taken during such times. Even though it is not completely dark, the artificial lights are well seen; the street lights, lights in the buildings and the lights of cars providing sublime scenery that plays a major part in the composition. This is the reason I am referring to evening and not morning twilight. During morning twilight most people are asleep, hence no lights in the buildings and offices; roads are almost empty with no vehicle lights to use as leading lines, or traffic trails as they are better known.
The question of exposure metering is something worth mentioning. There is no better or worse metering. My preferred method is spot metering. Take a metering from the brightest subject, whether it is the furthest traffic lights or a fully lit building and then add between +2/3 and +1.1/2 exposure compensation, depending on the camera you are using, and take a picture. Take a good look around the entire picture while previewing it and also keep an eye on the histogram. In this kind of photography you are more likely to burn out some highlights and this can be acceptable. When it comes to shadows, however, they should be captured as brightly as possible and with enough detail. Remember that very dark shadows from an underexposed picture are more likely to contain colour noise. Avoid this by overexposing the picture as much as you can in the camera. You can always correct the exposure later on in software. Another way is to take multiple exposures and blend them later for a more even exposure. Obviously, shooting raw will make a big difference instead of shooting jpg. Trial and error with different exposures is the best way to learn and gain the necessary experience to photograph these types of exposures successfully.
Natural and artificial light
The idea of shooting at evening twilight is to combine natural light and artificial light. If you shoot too early, the natural light is much stronger and the artificial light will not be dominant enough in the frame. If you shoot too late, the artificial light is too dominant; meaning the sky and other dark objects will be rendered too dark. Choosing the right time, when there is a balance between natural and artificial light gives the perfect outcome: the dynamic range in the frame is narrow, allowing for a much easier exposure to be achieved. Trial and error on timing is the best way to get more experience.
If you choose the right spot from which to shoot, for example over a bridge, and you use slow shutter speed, you can create very pleasant looking results with traffic trail lights in your picture that leads the viewer’s eye to the subject in your frame. It is even better if other elements such as reflections can be combined in the frame. Moving clouds, traffic lights, lit towers and reflections can all come together to create a very agreeable result.
A question that is frequently asked is how slow the shutter speed should be? My rule of thumb for cases such as shooting from the top of a bridge with cars crossing below is to measure the time it takes for a vehicle to pass the last two-thirds of the distance until it leaves the frame. This is the minimal exposure time. If you make the exposure shorter than this time frame, the outcome will be too many short lines.
What if the shutter speed cannot be as slow as we need it? In this case, we have to use filters to block the light falling onto the lens, enabling the camera to set a slower shutter speed. The best option here is the neutral density filter that comes in different strengths from 1 stop to 10 stops.
Consider the Eiffel tower. It has its projector lights on top. These lights are similar to the light of a lighthouse. It is a great opportunity to catch these lights under foggy or misty conditions. In such case, an exposure which is too long will render the light beam non visible. If you make the exposure too short, the light beam will be too narrow. The photographer should look and estimate a scene, understanding the speed of the moving light beam. In the case of the Eiffel tower picture, I counted the time it took the light projectors to light up the exact portion of sky I wanted in my picture, set my shutter to that time, calculated the aperture accordingly, and fired. My calculation was 1 second which had to be achieved in combination of f/3.5 aperture and ISO 400.
Originally, I imagined myself taking a photo of the Arc de Triomph from one of the balconies surrounding Charles de Gaulle square in France. Practically, and unfortunately, this was impossible and so I walked around the beautiful square unsure of the right angle. Finally, even though many experts say ‘do not centralise your subject’, I decided to do exactly that. I kept the symmetry by standing in the middle of the traffic. Cars came from the roundabout on my left, and went towards the roundabout on my right. I was standing right there, composing the street lights on both sides, with the extremely impressive and beautiful structure in the middle. In this case an exposure of 30 seconds was sufficient to allow for the traffic trails to be recorded accurately. Actually, I made a couple of exposures with my ND filter at first but as the time was passing by, it was getting too dark and there was no need for the filter. The lights of the traffic lead the eye towards the structure; it feels like a door opened towards the Arc de Triomphe.
Seascape and cityscape
If you have experience in seascape photography, you know that long exposures make moving water appear silky smooth. Even when there are waves and drama, the sea appears as a calm ocean. Combining this aspect with urban lights can enhance an image. Not only should you balance the streets lights with the available natural light but you should also open the shutter for as long as possible in order to get the ‘milky effect’ of the water; you may need the use of ND filters for such results. However, you need to be aware that moving objects on the water surface will appear blurry and might distract from the subject.
Less is more
Sometimes taking a picture of a busy junction can capture many aspects of a city: how busy it is, the rush hour and yet, capturing all this while keeping an order in the frame can be tricky. All you need is a good view of the junction; in my case it was a friend's apartment in the 20th floor, right above the junction. The composition is very limited, nevertheless I did not need much more than this. When you calculate the exposure for such a scenario, bear in mind that in this kind of scene you need to keep the shutter open as long as it takes for all directions of traffic to make their turn.
I hope I have imparted some ideas and advice that could be of use on your next outing to photograph cityscapes at twilight. The most important advice I would share with you is to gain experience! Do not be afraid to make mistakes as this is the best way to learn.