Max Dupain’s 1937 photo Sunbaker is up for auction and expected to fetch $20,000-30,000. Photo: Max Dupain/Mossgreen.

Max Dupain, the 20th Century photographer, gave Australia one of its greatest images, Sunbaker, quite by accident.

“We were camping down the south coast and one my friends leapt out of the surf and slammed down onto the beach to have a sunbake – marvellous,” Dupain said of the image he took nearly 80 years ago.

In a career spanning nearly six decades, Dupain, who was born in Sydney in 1911, and died in 1992, captured the city he loved, from famous beaches such as Manly, Newport and Bondi, to the landscape and its architecture, alongside portraits of famous people of the era, nudes, flowers and experimental modernist photos.

More than 500 photos from Dupain’s personal archive are going up for auction this weekend in what Mossgreen CEO Paul Sumner says is the most valuable and important photographic collection ever to be auctioned in Australia.

Dupain’s son Rex, also a photographer of renown, is selling the works, which are expected to fetch more than $1 million, with his 1937 work Sunbaker, carrying a price estimate of $20,000-30,000.

The auction also heralds the Melbourne auction house’s move into Sydney, with a new exhibition space and auction rooms at 36-40 Queen Street, Woollahra.

The Dupain images will be on show to the public for viewing from Friday, June 17, until the auction this Sunday, June 19, at noon.

The full auction catalogue of all 500 works is here.

Among those works, here are 25 incredible images of a Sydney now long gone, that many people have never seen before.

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