By the 1970s, it was considered sacrilege – a political act designed to taint a medium that was otherwise precious and pure.

But artist Micky Allan did it anyway, with no idea that she was being particularly subversive.

"I'd trained as a painter, but then I really liked photography because you could sort of engage with people in a different way," she said.

"It was before a lot of the studio photographers made very made-up situations and arrangements and all of that…Photographs had this very realistic kind of feel, and I wanted that more amorphous, irregular, unnameable thing that comes from the touch of painting."

Allan is part of a new exhibition at the National Gallery of Australia devoted to hand-coloured photography, with works by 12 other artists, including Julie Rrap, Fiona Hall and Jon Cattapan.

Senior curator of photography Shaune Lakin said the show had emerged from his long-standing interest in Australian feminist photography, particularly the work being produced in the 1970s.

"Micky was sort of the primary practitioner, really. She was the first Australian photographer after the Second World War, I would say, to go back to what was an historical process, which was putting colour over a photographic print, and it was a really political sort of thing to do at that time," he said.

"Certainly throughout the 1980s, Max Dupain, who was a regular reviewer for the Sydney Morning Herald, spent a lot of time criticising, in sometimes really hostile ways, the work of particularly women who were hand-colouring photographs. Not just women – for the canon, what Micky did was very troubling."

For Allan, though, it was a vital process of dialogue between two equally valid art forms.

"I remember when I was taking the photographs… in the darkroom, the thrill when it sort of comes up in the medium and you can't tell exactly what it's going to be, until it's sort of there. But it's not the same as the touch of painting it," she said.

"It's different, and it's different from an ordinary painting, there's something that you're in dialogue with, which is the person or the place or the whatever. So it's this really intimate connection that's making this new thing, that's not you or what you photographed, but a strange combination of the two."

Robyn Stacey, another artist featured in the exhibition, recalls taking classes with Allan at the Tin Shed at the University of Sydney in hand-colouring photographs, a practice she said was an integral part of being an artist in the 1980s.

"Sydney was kind of in thrall to post-modernism at the time, and one of the things about it was breaking down the barriers between high art and popular culture," she said.

"A lot of women photographers did hand-colouring - it was also the way of kind of personalising the mass-produced object, so a lot was this idea of using old-fashioned techniques and re-purposing them in the '80s.

"It really does coincide with feminism, the rise of women in photography in Australia in the '80s, punk, postmodernism – all those things came together with this idea of, what the hell, I'll just do it, because that was very much the spirit of the day."

Mr Lakin said that today, of course, the practice goes beyond feminism and punk.

"It's artists who are interested in mixing up photography and contemporary artists use photography in lots of different ways, so it's no longer a kind of provocation, it's become part of contemporary practice," he said.

"Aside from all of the interesting critical questions, the work is very, very beautiful. There's nothing like looking at something that somebody has laboured over, and it's not something that we necessarily see all that easily in photography, a surface that's been subject to really intimate and personal inscription or over-painting."

Colour My World: Handcoloured Australian Photography opens at the National Gallery of Australia on April 3 and runs until August 30.