Kurtz's "Rembrandt" style of light and shadow is suggested here. If this photograph is indeed by Kurtz, then it is from after 1865, when Kurtz first opened his New York studio.
For more information on William Kurtz, see "Notes on Whitman's Photographers."
Photographer: Kurtz, William, 1833–1904
Date: ca. late 1860s
Technique: photograph
Place: New York (N.Y.)
Subject: Whitman, Walt, 1819-1892 | New York (N.Y.)
Creator of master digital image: Library of Congress
Rights: Public Domain. This image may be reproduced without permission.
Work Type: digital image
Date: ca. 1995–ca. 2000