A second book is set to be released showing the reality of life inside Welsh hospitals during the coronavirus pandemic.
NHS employee and part-time photographer Glenn Dene worked with intensive care consultant Dr Ami Jones to capture the highs and lows behind closed doors.
Some photographs show moments of positivity, such as staff tenderly supporting each other through difficult moments, and babies being born.
But more harrowing images include Covid patients on ventilators and a body on a mortuary trolley.
The pair's first book of images - 'Behind the Mask' - was published in summer last year, with all proceeds supporting the Wales Air Ambulance and other NHS charities.
A second book featuring images from the second wave of the virus is set to follow.
Incredibly, Glenn - who works as an operating department practitioner across A&E, intensive care and operating theatres - has only been taking photographs for around six years.
His wife bought him a camera for his birthday and although initially unsure, he soon became "hooked" on the hobby.
When coronavirus took hold in the UK, front line worker Glenn realised he had a "unique" opportunity to document the reality of those alongside him.
With the permission of health chiefs, Glenn began to take his camera with him for his shifts in the hospital.
"It was a pandemic - we'd never seen anything like it in the NHS before," Glenn told ITV News.
"When this opportunity came along, it had to be documented really. The position I was in was quite unique - I photographed things I never thought I'd photograph."
Glenn has so far taken around 6,000 photographs across two hospitals - Nevill Hall in Abergavenny, and the new Grange University Hospital in Cwmbran.
"I've always got my camera in my bag ready to go," he explained.
"I feel very privileged to be given the opportunity and very pleased that people trusted me."
Glenn would work his own busy shifts before staying on for a couple of hours in his own time to take photographs as colleagues and patients lived through history.
"Mentally, it's been difficult to shut off from work," he admits.
'"Covid ruins people's lives. There are things that happened during the pandemic that will live with me forever. Mental health is going to be around long after Covid has gone."
Glenn never stages the photographs he takes, instead snapping moments as they happen.
"I'm very much a fly on the wall - I never ask people to pose or anything like that," he said.
"You can see how staff really are - those intimate moments with a patient, or when they've got five minutes to themselves."
Glenn says he has "so many" stand-out images in his collection, but one that always comes to his mind is of a hospital patient pointing at the word 'pain' on a chart.
Some moments he chooses not to photograph out of respect.
Glenn himself tested positive for coronavirus on Christmas Day.
Despite having witnessed the effects of the virus in work and through his camera lens, he was still shocked at how ill he became.
"It knocked me off my feet," he said. "My taste and smell went and I was bedridden. I've never been knocked off my feet like that."
Now recovered and back in work, Glenn continues to take photographs when he can.
Sometimes he uses his short breaks to capture the people around him.
Many of his photographs feature close-ups of the faces of NHS workers, fraught with worry.
But Glenn said as well as fear, you can also see "determination" in their eyes.
In particular, he credits consultant and co-author Dr Ami Jones with bringing the book to life through her words and recollections.
"She deals with life-or-death decisions," he said.
"We'd never experienced anything like this before. We're living through history."
Dr Ami Jones adds that she thinks it's important that people know what is happening behind closed doors.
"This is probably one of the worst - and also best - times in the history of the NHS," she told ITV News.
"The way that teams have come together to adapt and overcome is very positive - but it's clearly a dark time in the NHS. So sadness and happiness when you look back at the photos, really."
Although proud of his contribution to documenting history, Glenn said it is more important to him that people take coronavirus seriously.
"It doesn't matter to me that I took the images," he said.
"It just matters that people remember."
Video report by ITV Wales reporter Kate Lewis