A shared love of the environment has helped Laura Jones win the Archibald Prize for her portrait of author and conservationist Tim Winton.
A four-time Archibald finalist, Jones said she never expected to take out the prestigious prize.
She got the news of the judges unanimous decision from Art Gallery of NSW director Michael Brand just hours before the announcement on Friday.
"I can't describe the mixture of feelings. I was shocked, so happy and humbled," she said after receiving the $100,000 prize.
Jones, who becomes the 12th woman to win the Archibald, said she dreamt of being an artist as a young girl.
"I've been lucky enough to make that dream come true - more than any other event, today shows that I wasn't completely crazy," said the artist, who is based in Kurrajong at the foot of NSW's Blue Mountains.
Winton is the author of 30 books, including the Miles Franklin Award winners Cloudstreet and Breath.
Jones was inspired to paint the West Australian after studying the bleaching of the Great Barrier Reef as part of a residency in 2016, meeting him at an environmental advocacy event.
When she flew to Perth for a sitting with the author, the reef was suffering its fifth mass bleaching event in eight years.
"Tim was warm and witty. We spoke about the historical relationship between printmaking and political activism," Jones said in an artist's statement.
Jones said Winton rang her on Friday morning to congratulate her on winning the nation's most well-known art prize, first awarded in 1921.
"He made a joke that he thought he looked like he had the weight of the world on his shoulders, but he does and we all do," Jones said.
"I hope that we can all unite for the environment."
Winton said he was initially reluctant to sit for the portrait.
"I had seen Laura’s paintings of the Great Barrier Reef coral gardens, including her beautiful and tragic depictions of coral bleaching, so I was a little more curious and open than usual," he said in a statement.
The winning portrait was selected from more than 1000 entries and 57 finalists.
Also announced on Friday, Naomi Kantjuriny won the $40,000 Sulman Prize for her work Minyma mamu tjuta.
"I've been painting for 30 years, and I love it," Kantjuriny said in a statement read out at the gallery on her behalf by Tjala Arts chairperson Muna Kulyuru.
"The story of the mamu is a story we sing and dance to. Mamu are good and bad spirits, sometimes they hold scary stories that teach lessons to the grandkids."
The $50,000 Wynne Prize has gone to Yolŋu elder Djakaŋu Yunupiŋu from Yirrkala in the Northern Territory, for her painting Nyalala gurmilili.
"I am one of seven sisters. There are only three of us left now. The songs of this painting were given to me by our father, Muŋgurrawuy," she said in a statement after hearing of the win.
"It shows the songs of the seven sisters in the stars crying. Now I am crying. But this time with happiness."
Former graffiti artist Matt Adnate has already been recognised with the $3000 Packing Room Prize for his painting of Yolngu rapper Baker Boy.
The finalists will be on show at the gallery from Saturday until September 8.
They will then tour regional NSW and the Northern Territory.
