This is a long exposure photograph of Argentine tango dancers moving along the dance floor during a milonga in Atlanta, Georgia.
The exposure of this photograph was two seconds long. Because a tripod was not available, the camera needed to be held by hand. None of the people in the photograph were posing or otherwise in on the shoot. They were just going about their business. As such, it was on me to meet them where they were at, and to do so quickly before they began shifting around positions again.
I was wondering around when I noticed a semi-open view of the dance floor with an angle that I liked and an open chair inline with this shot. I was able to position myself behind this person as they were taking a break from dancing. Setting the camera down directly on a nearby table or chair was not an option. First, if I wanted to have someone in the foreground, positioning the camera that low would have obstructed the view of the dance floor. Second, I think shooting the photo at the eye level of a seated person helps the viewer see the scene as if they were there. As if they themselves were in the scene, seated behind this woman, looking up at the dancers as they glide along the dance floor.
That said, this made my life as a photographer more difficult. This required me to hold the camera high enough to get an unobstructed view. Meanwhile, I needed to use a long exposure to capture both the motion of the dancers and to get enough light for the exposure. In the end, I just had to do my best in the moment to stabilize myself using the environment around me.
As always, the most important thing is patience. People on and off the dance floor were in a perpetual state of motion. Almost everything about the scene was constantly shifting. Though, in the end and after several attempts, I managed to capture this photograph.
I really enjoy the way this photograph captures the movement of the dancers. Meanwhile, the woman seated in front of the camera remained almost completely still. This introduces contrast between stillness and motion, making the motion of the dances stand out that much more in my mind.
Long exposure photography, as the name implies, simply refers to photographs taken with relatively long exposure times. Typically, the photographer wishes to capture the movement of one or more elements within a scene over the course of the exposure. The resulting photograph then reflects this movement in some way. This technique can be used to create various effects, and thus is a useful technique for photographers to know.
Taking long exposure photographs can be a bit tricky. First and foremost, the photographer needs to imagine what is going to happen in the scene over time and how that will affect the final result. There are several technical aspects to take into account as well.
As with all forms of photography, managing the light in a photograph is important. Long exposure times can add yet another layer of complexity to lighting. Not only does the light build up over a longer period of time, but it may also move around and/or change in intensity. The exposure settings on the camera also govern how the movement will be captured, including how much overall movement is captured and how much each element of the scene contributes to the final image. Many factors, such as how bright an object is, how reflective it is (e.g. glossy vs matte), how fast it is moving, the use of flashes, and so on, all play a role in how an object will show up in a long exposure photograph.
Secondary effects, such as camera shake and sensor noise, have a higher chance of affecting long exposure photographs as well. Digital camera sensors tend to generate more noise when they are exposed for longer periods of time. Camera shake can become a factor as well. Even small, subtle movements can affect the sharpness of the image. For example, cameras are commonly placed near roadways when photographing the light trails created by cars driving at night. Vibrations caused by those cars can subtly and constantly shake the camera, introducing a slight blur in the final photograph.
More examples of long exposure photographs that I have taken can be found here.