Capturing Cityscapes During the Perfect 15 Subset of the Blue Hour

Following Sean's recent winter photography tip suggestion, I took the Canon 11-24mm f/4L Lens to New York City for a late-winter day. New York City is one of the most photogenic cities on the planet and it remains similarly so at all times of the year. Advantages of shooting architecture and cities when it is uncomfortably cold out include fewer people to interfere with your compositions, fewer photographers competing for the same shooting locations and easier isolation of composition-enhancing people while doing street photography.
 
Scouting
 
New York City is extremely large and I doubt that anyone will ever exhaust all of the photo possibilities of this location. For sure I will not. This means that pre-trip scouting is especially important. Using available online resources to visualize the location's available compositions maximizes one's photo time. These resources include maps, satellite imagery, The Photographer's Ephemeris, reviewing photos others captured at the potential location, etc.
 
Part of this scouting involves determining the direction of sunrise or sunset as this effects the look of the image at a key time of the day for cityscape photography. The sun rising or setting to the side of an image will be the most challenging with the sky taking on a brightness gradient from one side of the image to the other. If the sun is rising or setting behind you, buildings will reflect the brighter sky and the background sky will be darker in relation to the buildings. The sky may also become pink above the horizon in this situation. If the sun is rising or setting in front of you, the sky will be brighter in relation to the buildings, but the building lights will become more pronounced. Both latter options are great. My choice in this example was the in-front-of-me sunset.
 
On Location
 
Arriving at the location early to verify the choice made during pre-trip scouting is highly recommended. You never know what you might find upon arrival (such as a large construction project), so arrive early enough to implement plan B if necessary. Yes, having at least a plan B and, better yet, a plan C and D is a very good idea. Arriving early also provides the best opportunity to score the perfect shooting location.
 
On this particular cold evening, there was no competition for shooting location and to completely avoid the chance of people walking into my composition (and to avoid an ugly sign and construction fencing), I setup so that no foreground was visible in the frame. To do so at the focal length I wanted to use (24mm – the longest available on the lens I was evaluating) required extending my tripod down through the curved East River fencing.
 
The Right Time of Day Makes the Difference
 
City lights do not come on (or become visible) until it gets somewhat dark and these lights are a key to one of my favorite cityscape looks. The lights add life to the buildings and while cityscapes can be captured in complete darkness, I find that some color remaining in the sky makes a better image.
 
The "Blue Hour", by definition, lasts for 1 hour just before sunrise and just after sunset (use your online tool or phone app to find out when it happens at your shooting location on your chosen shooting day). However, the perfect shooting time, when the sky color balances with the city lights (and possibly reflections), lasts for closer to 15 minutes within that hour. I'll dub this time period the "Perfect 15" and I can usually narrow my ultimate preference down to a subset of that duration. While the Perfect 15 are ideal for capturing a variety of image types, cityscapes are an especially great use of this short period of time.
 
While it is possible to capture a number of compositions within the Perfect 15, I find it best to concentrate on one composition at the key time of the day. Fifteen minutes sounds like a very adequate amount of time to capture one image, but I assure you, it is often not. Here is why:
 
At this time of the day, each f/11 image requires 30 seconds of exposure (roughly) followed by 30 seconds of long exposure noise reduction dark frame capture. Add a few seconds for mirror lockup and multiply each shot by two or three for exposure bracketing (if warranted for HDR) and those Perfect 15 minutes begin to look very short.
 
Reflect a Great Scene for a Better Image
 
Want to make a great scene even better? Reflect it in water to double the greatness. Many major cities exist because of the water located by them, and cityscapes often look best when reflected in water. However, these waterways are typically large enough and have enough wind and boat traffic on them to never permit a mirror-smooth reflection. Reflections in rough water can look OK (though somewhat distracting), but making a smooth blur of the water via a long exposure is usually my preference. The Perfect 15 happens at the right time of day for long water-blurring exposures, but the boat traffic presents a problem.
 
Even during a 30 second exposure, the waves created by a large boat are going to create possibly-undesirable lines in the final image. Also, at this time of the day, boats are required to have lights on and those lights show very clearly as long streaks in the image. Sometimes these light streaks can be removed in post processing (try the content-aware healing brush in Photoshop), but lights on the larger boats (such as ferries) streak across the city details, becoming much more difficult to remove. When this happens, an available option is to simply leave the light streaks remaining in the final image, adding an effect. Most of the time, I find this effect undesirable. Correcting the uneven reflections caused by 30-second wave blurs is usually very challenging.
 
The Perfect 15 is Short for Even One Image
 
So, in addition to the over-1-minute exposure captures along with similar durations for exposure bracketed shots (for potential HDR use), a boat moving through an image can cut the remaining available time drastically. A tug boat pushing a barge through the Brooklyn Bridge and Manhattan Skyline scene takes a couple of minutes and the waves don't settle for a period of time after that. The East River Ferry is much faster, but it also makes significant waves. Boat traffic alone took a major chunk out of my Perfect 15 on this day.
 
Does the Tide Matter?
 
If your city's waterway is tidal-influenced and water-level subjects, especially in the foreground (such as pilings), are in your frame, make sure that your capture date is ideally timed with the tide. Use the tide charts available for your location to determine this.
 
The Weather Matters
 
If it were raining, snowing or foggy, I would not likely have been able to see the city I was photographing, so yes, the weather matters. Aside from being able to see the primary subjects, what the weather is providing becomes decreasingly important for cityscape photography at these times of the day. If you want the sunset to add a significant interest to the sky, there needs to be some clouds to catch color and an opening in the sky allowing the sun to illuminate those clouds. Since I wanted the city itself to be the primary interest in my image and because I wanted a high-percentage weather forecast, I chose a perfectly clear day for this trip. A clear sky provides a great blue color over the city and reflects in the water below it.
 
Seeing Stars and Aircraft
 
Cities are usually bright enough to overwhelm the visibility of most stars, but if you happen to be able to see the stars in your images, 30 seconds is probably going to give you some star trails. What to do with the handful of visible stars and their short trails is a matter of taste, but they appeared to be an anomaly in this image. There were not enough stars showing to make them appear as part of the scene, so I removed them.
 
Along with waterways, large cities usually have busy airports and air traffic very frequently becomes part of these images. The flashing lights from this aircraft generally create long dotted lines through a cityscape captured during 30 the seconds exposures typically in use during the Perfect 15. Again, the choice of what to do about these inevitable additions to the image is up to you. Fortunately, most of the aircraft are flying above the city and can be easily removed in Photoshop.
 
Replacing Light Bulbs
 
The waterways commonly found by large cities frequently have bridges over them. These bridges are often landmarks that you will want to incorporate into your images and these bridges commonly have many lights on them. The Brooklyn Bridge is one such bridge. After a severe winter, numerous light bulbs were in need of replacement. I'm sure that there had been very few maintenance crew members volunteering to scale the bridge under the severe temperatures (along with plenty of snow and ice) NYC had for many months prior, but I felt the missing lights negatively impacted the image and took the liberty of replacing the bulbs myself (in post of course).
 
Note that, while often the highest location in a city, bridges would seem to be great vantage points for cityscape photography during the Perfect 15. Unfortunately, for bridges with traffic on them, this is not the case. The amount of movement on most bridges with vehicular traffic is incredible (especially the large suspension bridges) and long exposure images captured from such bridges are typically very blurry.
 
This New York City Image
 
While reviewing the Canon EF 11-24mm f/4L USM Lens, I wanted to put some on-location hours behind this lens and decided that Brooklyn Bridge Park, just across the East River from downtown Manhattan, would be a good destination. I arrived early in the afternoon, spent an hour or so selecting what I thought was the ideal composition for capture during the Perfect 15 and then explored the area for other photographic opportunities.
 
About 45 minutes before sunset, I came back and anchored myself into the selected shooting location. I setup the camera, perfected the framing using a completely level camera (keeping the buildings vertically straight) and then established the proper focus distance setting. While I have yet to take a miss-autofocused image with this lens, I wanted no chance of that happening when the scene became dark. I used autofocus to get the initial setting, switched to manual focus mode and took a verification image.
 
While my selected image was captured 41 minutes after sunset, I captured images periodically before entering the Perfect 15. Some of these images are very nice and I'm glad to have them. More importantly, these images allowed me to monitor the exposure settings and how they were changing. There was no question about what settings I should be using when the ideal shooting time came.
 
While I did some bracketing and captured many exposures before, through and after the Perfect 15, everything came together in one image this time. The boat traffic stopped long enough for the waves to even out. The brightness in the sky leveled with the brightness of the city lights and the brightness of the reflection seems just right to me.
 
Aside from some of the tweaks I mentioned already (such as replacing burned out light bulbs), this image is basically right out of the camera. I shoot with the Neutral Picture Style selected in-camera to get a lower contrast histogram to best show the camera's available dynamic range and how I'm making use of it. Because this style's low contrast is not typically what I'm processing for, my usual first post processing step is to select Standard Picture Style. I added some saturation and turned the sharpness setting down to "1". Even with a very low "1" sharpness setting, all details in this image are tack sharp. Awesome lens.
 
Other "Perfect 15" Cityscapes
 
A few other recent cityscape images can be found here:
Pilings, Brooklyn Bridge Park, NYC Skyline at Sunset
Capturing the Spirit of Baltimore's Inner Harbor
Manhattan Skyline and Hamilton Park
 
Summary
 
A majority of photographers and other observers pack it in when the sun dips below the horizon, but the show is just getting started at sunset. Stick around. If the sun is visible in the sky, unfortunately, the best AM photo time may be in the past. This is the time to make plans for tomorrow. Try shooting during the blue hour and learn what your "Perfect 15" is.