By Liz Hobday in Melbourne

A masterpiece by Australian impressionist Arthur Streeton not seen by the public for 130 years has been unveiled.

The 1894 oil painting Sunlight at the Camp 1894 has gone on show in Melbourne before its auction in Sydney, where it’s expected to fetch up to $1.5 million.

The work was highly significant in Streeton’s career and in the history of Australian art, chairman of Smith and Singer auction house Geoffrey Smith said.

“Very few works of this subject, date and scale remain in private ownership and its re-emergence for public auction represents almost the last opportunity to acquire a work of such beauty and stature,” he said on Wednesday.

Streeton was one of Australia’s most influential landscape painters and a leading member of the Heidelberg school with fellow artists Tom Roberts, Frederick McCubbin and Charles Conder.

Their work later became known as Australian impressionism, the nation’s first distinctive movement in painting.

Streeton painted Sunlight at the Camp when he was in his late 20s and living frugally in an artist’s camp at Sirius Cove alongside Tom Roberts, in the newly established municipality of Mosman.

It was the golden age of Australian impressionism, a time when the most creative visual artists in Australia worked side by side to record the landscape they were immersed in, said Smith, painting directly from nature in a way that would change the course of Australian art.

“It was that idea of Australians painting Australia, capturing the moment and the essence of a place and a time,” Smith told AAP.