For someone who says 99 percent of street photography is about failure, Alex Webb has had a notably successful career. From his early work in Haiti and along the United States-Mexico border, to recent projects in the United States Rust Belt, Mr. Webb, a member of Magnum Photos, had produced a deep archive of images rich in color and complexity. James Estrin recently discussed with him how his work has evolved over the last four decades. Their interview has been edited.

Q.

You’re known for making complex images that seem to other photographers as if they would be very difficult to compose. How do you work on the street? How much planning and forethought go into making your images?

A.

I take complex photographs because I experience the world — particularly more and more as I get older — as a very complicated and ultimately inexplicable place. My experiences in the world, my travels as a photographer, lead me to believe that there are no simple solutions, no easy answers, just a lot of difficult and perhaps unanswerable questions.

My most basic process as a photographer is to wander, allowing the camera and my experiences to lead me where they will. I try to arrive initially in a situation, or a place, with as few rational preconceptions as possible. Of course, that is ultimately impossible; we all are conditioned by our culture, our education, our experiences — what makes us who we are. Nonetheless, I make an effort to be as open as possible to alternative possibilities, possibilities that may contradict what I rationally might expect.

The words “planning and forethought” imply a level of rationality. Instead, I sense the possibility of a picture. It might be a group of people, it might be the look of a corner, I can’t say what it might be until I see it. It’s all about having a feel for the street.

My photography at its purest is about response, about visual exploration, about discovery. On one level, if I knew what it was I wanted in advance, I’m not sure I would choose photography as a medium. Part of what excites me about photography is its very uncertainty, the fact that it is not just the photographer, but the vagaries of the world that result in the photograph. If I had a greater inkling of just what I wanted in advance, why not choose a medium where there is much greater imaginative control, like painting?

Q.

When you come across a scene that interests you, how are you thinking about composition and color?

A.

I feel the space, the light, the color, the form and the scene simultaneously. I’m not thinking, I’m sensing the street. For me, color isn’t just about color, light isn’t just about light, space isn’t just about space, form isn’t just about form. I’m intrigued with the emotional and sensory tenor of these elements.

Q.

Like most everyone over 50 you started out shooting black-and-white. Was there a specific time when you started to understand the way color could work for you in your photos? Other than the obvious, how was it different than making black-and-white photos? Why haven’t you gone back to black-and-white?

A.

Working in color evolved directly out of where my photography led me. In the late ’70s I found myself drawn towards photographing in Haiti, elsewhere in the Caribbean and along the U.S.-Mexico border. But I felt that something was missing in my black-and-white: a sense of the searing light and vibrant colors of these worlds. Unlike the gray-brown reticence of my New England background, intense color seemed an integral part of these worlds. Because of where I had chosen to photograph, I stumbled upon a way of working in vibrant, saturated color.

In many ways I feel very close to the tradition of black-and-white street photography — certainly that’s the tradition I come out of. I find, however, that color adds another element, another note, something I still find exciting and fascinating.

Q.

A colleague of mine uses the term “organizing a picture” when talking about composing. Do you organize pictures? Arrange them? Find them? Channel them?

A.

Ultimately, the process of photographing in the streets for me is mysterious and exploratory. Why did I happen to have my camera to my eye when a boy jumped off a wall in a little Mexican border town called Boquillas? Why did I turn a corner and wander into a particular barbershop near Taksim Square in Istanbul when I did?

That said, remember that street photography is 99 percent about failure. It’s not just up to me whether a photograph will be successful. The world is my collaborator as well. I believe it was Charles Harbutt, in his afterword to “Travelog,” who wonders when he’s looking for a photograph if perhaps that same photograph is also looking for him.

Alex Webb/Magnum Photos

Q.

What’s the relationship of documentary or journalistic content and purely aesthetic concerns in your work?

A.

It’s always both for me, simultaneously and inseparably: vision and the world, form and content.

My work is questioning and experiential, so whatever political or sociological stances I have about a place I photograph come out of walking the streets of those worlds.

Additionally, my projects often change as I work deeper into them. For instance, I started to work in Haiti long before the demise of the Duvalier regime. In 1975, I had read Graham Greene’s “The Comedians” (set in Haiti) — a novel that fascinated and scared me — and decided to go to Haiti. Those first trips I photographed everyday life. Eleven years later when I returned to Haiti, the country was descending into turmoil after the ousting of Baby Doc Duvalier. As a result of the situation, my work changed. The book I ultimately produced, “Under a Grudging Sun,” turned out to be a kind of journalistic report on two very troubled years of Haitian history.

Yet it also was a very personal report of this difficult and sometimes violent time in Haiti’s history. During this tumultuous period, I was often confused, startled, uneasy and sometimes scared. My photographs from Haiti tend to reflect those states of mind — complicated frames, truncated figures, photographs that tend to raise complicated questions rather than to provide easy answers.

Q.

How has your compositional approach changed over the years?

A.

I don’t think that my compositional approach has changed significantly since I first started working seriously in color in 1979. Over the past 20 years, however, I think my work is more psychologically and emotionally complicated — which may partially reflect my life experience of being a father and a husband, losing my parents and seeing more of the complexities of the world — but my work isn’t necessarily more visually complicated. That depends on the place I’m photographing. For example, my Istanbul work — done between 1998 and 2005 — is perhaps my most consistently visually complex work, not simply because it’s later work, but, more importantly, because Istanbul is such a richly, multilayered city.

Q.

How does it differ in color and black-and-white?

A.

Now, having worked for many years in color, when I look at a scene, I am sensing not just what seems to be “happening” in front of my eyes and the various shapes that fill the frame, but I am also acutely aware of the colors, their relationship and their emotional and sensory resonances. Working in color has made me more attuned to the quality of light. In my early black-and-white work, I didn’t pay a lot of attention to the nuances of light. I’ve since become much more aware of the color of light, the angle of light: how a shaft of light, or a particular tone of light, can utterly transform a situation and hence the resultant photograph.

That said, I am in the midst of a joint project with my wife, the photographer Rebecca Norris Webb, in Rochester. It’s a kind of photographic exploration of this upstate New York city during what may very well be the last days of Kodak and perhaps even film itself. Since film has played an integral role in my and Rebecca’s creative lives — including helping us to find our own particular ways of seeing photographically — the project also includes a meditation on film and time and memory.

For this project, which we’re calling “Memory City,” I am shooting some black-and-white — as well as color. Interestingly enough, this black-and-white has a particular meaning in Rochester, the home of Kodak, which declared bankruptcy [last year]. I am using my last rolls of Kodachrome — the discontinued film I used solely for some 30 years. These days, Kodachrome can now only be processed as black-and-white, which gives the film a slightly distressed quality, as if weathered or faded over time. It seems appropriate for this project that explores Rochester and something about memory, time and the possible disappearance of film.

Alex Webb/Magnum Photos

A traveling exhibition of Mr. Webb’s work, “The Suffering of Light,” is on display through May 4 at Brigham Young University, where he will also be speaking on March 27. The book version, published in 2011 by Aperture, will be reissued this spring.

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