Photographs by one of the greatest American photographers of the last century have been bought by the National Galleries of Scotland.

Entering a public collection in Scotland for the first time are nine images taken by Paul Strand (1890-1976) in the Outer Hebrides.

The brooding black and white images will go on display until until September 20 at the Scottish National Portrait Gallery.

The acquisition, which cost more than £37,000, a deal supported by £20,000 from the Art Fund, and is composed of nine vintage black and white portraits of Scottish lives and landscapes in South Uist.

The galleries say Strand is ranked among the most important artists within the history of photography.

In 1954, after hearing a radio programme on the Gaelic songs of South Uist, he decided to travel there along with his wife, Hazel Kingsbury Strand.

Having been introduced to the islanders by the local doctor, Strand spent three months taking over a hundred photographs of the island and its people for his book, Tìr a’ Mhurain (1962).

Taken from a Gaelic song, the title translates as ‘Land of Bent Grass’.

Strand photographed many of the people in and around their homes, often posing them in front of a weathered wall.

In the group purchased, there are four portraits that show the sitters looking directly at the camera.

Five photographs show the evocative landscapes of South Uist; a loch and lilies, a croft, and ropes and a buoy used by the local fishermen.

Strand believed the islanders represented the "universal struggle of humanity".

Christopher Baker, director of the Scottish National Portrait Gallery said: "These works are an important contribution to broadening our international holdings of photography, while the distinct Scottish subject matter relates to the larger mission for the Scottish National Portrait Gallery in representing the people and topography of Scotland."