The Altering Eye marks the twenty-fifth anniversary of the founding of the National Gallery of Art's photography collection, celebrating the vitality, breadth and history of its holdings. In 1949 Georgia O'Keeffe gave the National Gallery of Art, Washington an extraordinary gift: a collection of more than 1,600 Alfred Stieglitz photographs known as the Key Set, the largest and most complete collection of his work in existence. It was not until 1990, however, that the Gallery actively began collecting photographs. Under the stellar leadership of Sarah Greenough, senior curator and head of the department of photographs, the Gallery's collection has expanded to nearly 15,000 American and European photographs dating from the invention of the medium in 1839 to the present day.

This richly illustrated volume features some of the most significant and compelling photographs the Gallery has acquired over the years and also charts the development of photography throughout its history, revealing the beauty and multifaceted nature of the medium. Following an essay by Sarah Greenough on the changing position of photography within the art museum and the development of the National Gallery's own collection, the book includes four essays by Greenough, Sarah Kennel, Diane Waggoner and Andrea Nelson tracing the evolution of photography over the past 175 years. In addition there are twenty-three shorter essays by Greenough, Kennel, Nelson, and Waggoner, along with Philip Brookman, focusing on some of the medium's most distinguished practitioners, including David Octavius Hill and Robert Adamson, Julia Margaret Cameron, Eadweard Muybridge, Eugène Atget, Alfred Stieglitz, André Kertész, Ilse Bing, Robert Frank, Gordon Parks, Robert Adams and Rineke Dijkstra, among others whose work the National Gallery holds in great depth.

In 1948 Georgia O'Keeffe wrote to a friend, 'Stieglitz worked for the recognition of Photography as a Fine Art - The Gallery means something in relation to that.' This volume and its insightful texts by the Gallery's photography curators is testament that indeed it does.