Speaking from her home, Ruth Medjber is feeling suspiciously serene – despite the imminent arrival of her book. "Everything is so organised that I think I've forgotten something," she laughs. "Usually, when I do exhibitions, I'm doing everything myself. But because of the book, I have a team of people helping me. I have an editor and a publicist, so I feel really lucky this time around to have a publisher."

Medjber's name has become synonymous with top tier concert photography over the last few years. After touring with both Hozier and Arcade Fire, Medjber entered a world of uncertainty in March 2020, when Ireland was first plunged into lockdown and her career ground to a screeching halt. That is, until lightning struck. Medjber developed a plan to photograph her friends from inside their houses at twilight. Word of mouth is a powerful thing, and soon she had 150 portraits for Twilight Together: Portraits of Ireland at Home. The work is a poignant and intimate exploration of the ways in which the pandemic affected the whole of Ireland, from young to old.

"I think it was the loneliness and idleness of lockdown that spurred me on to do this work," says Medjber, who lived alone for the whole of the lockdown. "If I had had a partner, I probably would have been happy in their company. It did force me out of the house, and forced me to think of new ways to get that connection."

Medjber began mapping a route each day to travel, photographing as many houses as she could in the short space of time that twilight allows. Luckily, she's no stranger to working at this kind of pace. Normally, during a tour, she would have to turn photographs of a concert over to bands and record labels almost immediately.

"I'd shoot the show, they walk offstage at 11 o'clock, and some bands would want images before people get home from the gig," she says. "And then the rest of the night I'd be working on the video, or processing the rest of the images that go out to the press. I'm used to working all hours of the day, all days of the week.

"When I was putting this book together, I worked every day for three and a half months. I was racing against the lockdown clock. I knew that lockdown was going to end soon enough, and people would be out of their homes, and not there for me to photograph," she continues. "So now, I've been waiting here, sitting on my hands, and dying to show everyone since August, when the book went to the printers. I'm so delighted now that I can show the world what I've done, and terrified that they won't like it."

But I don't think she needs to worry. Twilight Together may be a time capsule of a moment, but its execution is intimate and warm. She captured the best parts of the lockdown as well as the worst: disconnect, chaos, weddings on pause, and profound loneliness are combatted by community, family, and enduring love and patience.

"It's a book that's full of highs and lows, and I wanted to make a conscious effort to show the rhythm through the book, and I had to do that through the imagery."

One of the Medjber's strategies to achieve this was to allow her subjects to control their own portraits.

"That's a big thing about my practice in general. I tend to not direct people for portraits, because I think their own view of how they should be represented is crucial to them and their image. I told them what to do in terms of lighting, but that's as far as I went with directing and controlling these shoots. Everything else was up to the people and their personalities.

"I think that's crucial when you're doing a representation of a people," she continues. "You do have to let everybody's personalities shine through their own windows. It was kind of organic how that happened, but it's very much part of my style as well, to let people bring what they want to it. A portrait should always be a collaboration between the photographer and the sitter, and that's what you're seeing in this collection."

So – does she have a favourite portrait?

"There's a 150 houses and 499 people," she laughs, "and I couldn't for the life of me pick a favourite! I have a favourite to match each mood. When I'm feeling really sentimental and emotional, I look back at the warm loving couples – especially the older couples who are obviously still madly in love. There are the really giddy ones where people are drinking and laughing and dancing, and then there are poignant ones where we touch on direct provision and Black Lives Matter. And then of course, there's a lot of my friends in here as well. School friends, neighbours, friends in the music industry that I missed."

Although there are frequent moments of levity in Twilight Together, the photos that look toward the future are the ones that hit hardest. "I have a friend who feature in the book twice, once when she is 9 months pregnant and then a couple weeks later when she has the baby in her arms," Medjber recalls. "For me, the importance of that picture is extraordinary, because it's that child's start in life. Now that Elliot is born, I'm hoping that when he's 18 and he looks back, he has this sentimental document of his birth.

"And then there's Bumblebee (Beth), who is the baby in the very first photo. She's my friend Maeve and Paul's daughter. She was only six months when this whole thing started, and now she's a year and a bit. I texted them the other day when I realised Bumblebee has spent half her life in lockdown. That's bloody bananas, for these children."

Perhaps most importantly, this experience has been a learning curve for Medjber herself.

"I used to be quite a controlling person, really. I wanted to launch my exhibition on the 5th of November, and I wanted to invite guests in to visit the living room one household at a time, to coincide with the book launch. And then, of course, the government said 'actually, you can't.' And it was something I had absolutely no control over, so I've learned to have a plan B, C, and D, and just roll with it. It's not learning when to admit defeat, but it's learning when to concede, adapt, and change everything."

• 'Twilight Together: Portraits of Ireland at Home' is out now.