Stefan Ellis was a senior in college in Massachusetts when he decided to travel to Thailand to photograph the crowded Cambodian refugee camps on the border in 1986. He was inspired, like many, by a film.

“My son, like a lot of Americans, saw The Killing Fields . . . He realised then that the camps were still going on,” his father, Bob Ellis, recalls. “So he wrangled some press credentials and did it.” Stefan spent nearly four months documenting the conditions in Site Two and Site Eight, the latter of which remained under the control of the Khmer Rouge.

“According to [Stefan], they would take you in and show you [around] but not let you get behind the scenes,” Ellis says. Stefan Ellis later returned to Southeast Asia as a freelance photographer – he had also worked in Russia and Israel – before becoming an AFP photo editor in Hong Kong and establishing the wire’s bureau in Phnom Penh in 1991. Tragically, he took his own life five years later, at the age of 31.

But many of the photos from his first outing a decade earlier have been buried in boxes with his father in California since then – at least, until now. “I’ve just been sitting on them, and I’ve been starting to realise that a lot of the story of the camps hasn’t been told,” Ellis says.

The family donated the collection of 49 black-and-white photographs to Phnom Penh’s Bophana Center, where 21 will go on exhibition this evening. The work captures not only the conditions in the camp, but also the powerful stories of those who lived there.

“A lot of these were families who lived there for years and really didn’t know any other life at that point, [and] quite a number of them could still be alive today,” Ellis says. “He worked very hard to get people in the camps to feel comfortable. They were very suspicious of Westerners, especially in Site Eight – there were always soldiers lurking in the background,” he adds.

Stefan’s photographs from the camps are more than a simple documentation of people, time and place. His portraits of families and individuals are a powerful testament to humanity’s resilience in the face of disaster.

One portrait in particular, of an expectant mother named Seng An, had a lasting impact on Stefan. He included her in a note to his friends and professors: “No one had the right to see her in such pain. It came home to me at that point just how limited journalism was, as I would never be able to bring home how much pain she was in and just how serious the KR problem was,” he wrote.

“She stopped crying eventually and looked over at me and told me, through the translator, ‘Please take my picture. I want you to tell people in your country about how the Khmer Rouge killed my family’.”

“I thought of all the things I had ever wanted or striven for and then about the suffering and the unheard cries of the Cambodian people and knew that I would never be the same again.”

Thai Border Cambodian Refugee Camps opens tonight at 6:30pm at the Bophana Center, #64 Street 200. The exhibition runs through January 16.