Throughout my career in photojournalism, it was rare to find out who the people in my photographs were. For routine assignments, news photographers can ask subjects their name and other information, which is important for captions.
The rush to capture the event and the deadline pressure to file the photos does not often allow photojournalists to stop and talk to their subjects, certainly not when they have the responsibility to document a disaster like the September 11 attacks.
It is often impossible or unsafe to do this.
But an image from September 11, 2001, taken for Agence France-Presse (AFP), was different.
On the day of the attacks on the World Trade Center in New York City, I photographed a woman covered in dust after one of the towers fell.
It later became one of the iconic photos of 9/11.
It was the one frame I took of her as people took shelter in a building lobby from the giant cloud of dust and debris that had enveloped the area after the first tower collapsed.
She was wearing a business outfit, the dust obscured the colour of her clothes and boots, her necklace reflected the lobby light. Her arms were held out as if she was gesturing towards me.
The image is yellow in tone; this was not intentional. I had my camera set for sunlight and the indoor artificial lights added a yellowish cast. Later that day, in the rush to file the photo, I didnâ€™t correct the colour cast and when I saw it in print, I noticed how the colour seemed to convey a sense of doom, a sense of dread.
The second after taking the photo, I saw her being helped by other people to a stairway, presumably to a safer location. I thought I would never see her after that.
But in the days and weeks after September 11, I did wonder who she was.
It was a day that could only be described as completely chaotic.
An AFP photographer called to tell me that a plane had just crashed into the World Trade Center. We both assumed it was a small private plane.
I got on a subway train in the morning rush hour from my Manhattan apartment to the City Hall station. The train ride seemed to take forever, longer than the usual half hour.
There were delays on the New York City subway, quite possibly caused by the emergency in Lower Manhattan at the time.
I finally arrived at City Hall after about 50 minutes.
Up on the ground level, I saw hundreds of people standing and staring at the twin towers, a few blocks away. The top floors of both towers were on fire by then. I hadnâ€™t heard about the second plane crashing into the South Tower, so I was very confused.
I shot several photos of the crowd and the towers and headed towards them to take more.
I made my way south and could see huge crowds of people running north, away from the buildings. There was a constant din of sirens as emergency vehicles sped towards the area.
As I got close to the towers and was shooting one of the buildings, I heard a big roar, like a train, followed by thick clouds of dust and smoke. The first tower had collapsed.
I was just a few blocks away from the World Trade Center, photographing the towers as they were falling apart.
Billowing smoke hung in a haze between the buildings around me, people were running out of the clouds. Then it turned dark, dark as night, as denser smoke and dust filled the air, making it difficult to see.
I went towards a nearby office building where I could see a police officer ushering people in and joined them to escape the smoke.
A few people were standing in the lobby, shock and confusion on their faces. A minute or so later, a woman walked in, completely covered in dust. I instinctively photographed her and headed back outside.
Some of the smoke had cleared by then. It looked like it had just snowed. Everything â€“ the street, the buildings, the cars, and even the people â€“ was completely covered in light grey dust.
It was eerily quiet as people walked through the rubble.
I continued to capture the scene, shooting images of people helping each other and trying to get out of the area. A city bus stopped to let people on without taking any fares. I photographed a man walking through the debris in a business suit, still holding his briefcase. That would become the second widely used photograph of mine from that day.
The days that followed
A few months later, in early March 2002, an AFP editor in the Washington, DC, office called me to say they had traced the woman in the photo.
Her name was Marcy Borders. Her family had seen the image, which had been published in several newspapers, magazines and on websites around the world. They found a phone number for the AFP Washington bureau and confirmed the womanâ€™s identity to an editor.
I worked out of the New York City bureau and was amazed to hear that we now knew who the woman in the photo was.
I realised I wanted to meet her.
Michel Moutot, who was AFPâ€™s New York bureau chief â€“ where I worked out of â€“ and I arranged to meet Borders at her apartment in Bayonne, New Jersey on March 8, 2002.
While I was thinking it was incredible and unbelievable to actually meet this person I had photographed on that historic day, I was also relieved to see that she was physically fine.
There had been so much death and destruction on that day, hearing a survivorâ€™s story was uplifting.
Borders had had a tough life until she got a job in 2001 with Bank of America, whose offices were in one of the twin towers. Her life seemed to be moving in the right direction.
But that all changed on 9/11 â€“ a plane crashed into the North Tower. She worked on the 81st floor and managed to escape before the building collapsed.
We listened intently, trying to absorb it all. I took a few photos in her apartment; she had a small American flag attached to the outside of her front door.
She seemed very much affected by the experience, frightened to even hear the sound of an aeroplane, so afraid of tall buildings that she vowed not to return to Lower Manhattan.
It was sad to see her that scared. It seemed unfair that she may lose her job because she would struggle to overcome her fear of going inside a tall building again.
I met her one more time during a television interview but we did not stay in touch. Through the years I would see media interviews with her on 9/11 anniversaries.
I took hundreds of shots that day but the photo of Borders is the one that is featured across various publications every year on 9/11.
The image reminds me of just how chaotic and confusing that day was. Iâ€™m surprised I made it out without being injured.
Her story is one of thousands of the people who survived 9/11. Perhaps people can relate to it as it shows a person trying to deal with the chaotic situation they found themselves in.
For many people, I think the photo humanises the experience.
I was very sad to hear that Marcy died in August 2015 of stomach cancer.