The man tilted his head back and laughed -- his hands and shirt covered in grime from mucking out a Hurricane Katrina-damaged home in the Gentilly area of New Orleans -- and said, "Man, you have your work cut out for you." He wasn't kidding …

A few weeks earlier, Blake Sell, editorial director at World Picture Network, sent me an e-mail asking whether I'd be interested in returning to New Orleans to shoot the "after" half of a set of "before and after" photos. Basically, WpN would provide me with a bunch of great images taken during and immediately after Hurricane Katrina by a variety of WpN contributors and I would return to the exact same locations and take the exact same picture. Another WpN photographer, Zoriah, had produced a similar set of "before and after" work from the tsunami in Phuket, Thailand. It graphically illustrated how quickly Thailand has recovered from the effects of the tsunami.

Canal St. in New Orleans, La., on Saturday, May 20, 2006. Max Whittaker / WpN

"Sure," I said, thinking the assignment sounded easy. Having worked in the area just after Katrina struck, I figured this would give me a chance to check out the rebuilding progress in New Orleans. I knew it might be difficult to find some of the locations but the shooting would be easy, right? I was just copying another photo, after all. I'd just jump out of the car, snap a couple frames and then move on to the next one. An easy assignment.

Blake e-mailed me hi-res versions of the photos WpN wanted me to revisit, and I made 8x10 prints of them before packing up and flying to New Orleans. These prints ended up being the most important tools for this assignment.

Jay Williams sails down Canal St. in New Orleans, La., searching for basic necessities in the aftermath of Hurricane Katrina on Tuesday, Aug. 30, 2005. Matt Rourke / Austin-American Statesman/WpN

My first problem was the limited location info in the captions. For the most part, it was limited to "New Orleans," which didn't really help. Fortunately a good number were of obvious landmarks such as the Superdome, Canal Street, or the French Quarter. A few listed street names but I soon discovered most were incorrect. I was left to find the majority through visual cues in the photographs and the gracious assistance of the residents of New Orleans.

I started at my hotel, showing the desk clerks the prints and asking where they thought the pictures were taken. I repeated this endlessly with waiters, gas station attendants and random people on the street. Using this information I'd narrow down the location and then just keep asking, and driving and questioning -- for six days – until I found them.

Unfortunately, there were locations I never found. In the Gentilly area, the man laughed, gave the best advice he could and shook his head as I drove away. I never found that location.

Aerial photographs of the devastation caused by the high winds and heavy flooding in the greater New Orleans area following Hurricane Katrina on Tuesday, Aug. 30, 2005. Vincent Laforet / The New York Times/Pool/WpN

My second problem was making the pictures visually similar to the originals. This was much harder than I had anticipated. Composition, angle, lighting, lens choice and even sensor size were all factors I had to take into account. Some photos contained the original EXIF information including focal length and aperture. While this was helpful, I found myself trying to calculate the lens aspect ratio from another photographer's Nikon D1H to my Canon 1D Mark II. I'm not a techno geek and math is not my strong point. One day around noon, disoriented in the Crescent City (yes, the streets curve – not a grid like most cities), I asked three separate people which direction the sun rose from in order to get the lighting correct. One didn't know and the other two gave different answers. Unsurprisingly, it took four tries to get the correct lighting for one picture and two tries on many others to get the right perspective.

Aerial photograph of one of the canal wall breaches that flooded New Orleans, on Monday, May 22, 2006. Almost nine months after Hurricane Katrina struck New Orleans, the process of rebuilding has barely begun. Max Whittaker / WpN

Often as I struggled to find the shooting location of the original photographer I'd discover that it was in the midst of busy Interstate 10 (which, of course, was totally deserted immediately following Katrina) or standing in a boat floating on 4 or 5 feet of water. I got used to the idea of dashing into gaps in traffic to snatch a couple frames before lunging back to the curb or parking my rental car on streetcar tracks and standing on it to get the right angle for the photo. The problem was compounded during a helicopter flight because the pilot couldn't fly lower than 500 feet due to FAA regulation even though it was obvious that the original photographer had no such constraints during the chaos following the storm.

Though finding the precise locations at the right times proved more difficult than I had anticipated, I found the people of New Orleans to be helpful and generous with their time. These people gasped or teared up as they looked at the prints, but they told me how important it was that I document the rebuilding or the lack of, as they often scoffed. I began to feel like this very "mechanical" assignment was important, equally as important as the documentary stories I usually pursue.

I was somewhat surprised to see rebuilding has been slow and often nonexistent since Katrina. Sure the water was gone and some trash picked up, but destroyed homes were still just piles of rubble, a burning building was now a vacant lot, a flooded car was now on blocks, a hotel's blown-out windows were covered in plastic and blue FEMA tarps covered damaged roofs. Everything seemed on hold, as if people are waiting for something.

Hurricane season begins again this month. The New York Times reports that the canals are repaired but doubts remain about New Orleans' ability to withstand another Katrina-sized hurricane. Maybe it is these doubts that keep residents and agencies from achieving the kind of rapid rebuilding that Phuket, Thailand, has achieved. My only hope is that in the future I can return to these same locations and capture a revitalized New Orleans, not one slowly decaying or ravaged by storms.