A black and white portrait of a Byron Bay woman known as Feather has won the 2015 National Photographic Portrait Prize People's Choice Award.

The photo, 'Feather and the Goddess Pool,' was taken by Lennox Head-based photographer Natalie Grono.

"I love the fact I've won the People's Choice because I want my work to resonate with people," she said.

"And this shows that people loved the photo or were touched by it somehow.

"To win the judge's choice would've been great too, of course."

The winner of the judge's choice was 'Portrait of Ali' - photographer Hoda Afshar's photo of a boy in northern Iran.

Ms Grono said she photographed Feather at Byron Bay's Little Wategos Beach where she swims daily in what she calls the 'goddess pool.'

"Feather is in her mid 70s and I met her, fell in love with her, and asked if I could photograph her," Ms Grono said.

"She told me about this daily ritual she has, so I tagged along with her one day."

Ms Grono said she believed Feather's confidence was what appealed to people who chosen her photograph as their favourite in the contest.

"She's really comfortable in her own skin and that's magnetic," she said.

"I think people were excited about it because it's not every day you see a woman of her age in a bikini like that and so confident.

"As she says, 'life's not a rehearsal, this is it.'"