Judy Dater, Imogen and Twinka at Yosemite, 1974

Gelatin Silver Print. 9.5 x 7.5 in (24.1 x 19.1 cm) Signed on recto. Estimate: from $6,000 to $7,000

Note: An iconic image of the great photographer Imogen Cunningham and her model, Twinka Thiebaud, in Yosemite, 1974. This is Dater's most famous work, depicting Imogen Cunningham, one of the pre-eminent photographers of the twentieth century. From Cunningham's early work, which epitomized the soft-focus, painterly style of Pictorialism, she led the way to photography’s unique new vision, the Modernist movement. Her love of form and abstraction, and for the clear, revealing eye of the camera lens, gave her an extraordinary artistic vision that never faltered during a career that spanned more than seventy years.

This photograph was taken in 1974 and printed later.

Artnet Auction. Thursday, August 20, 2009, 4:00 PM EST. www.artnet.com