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Winterhalter's portraits were prized for their subtle intimacy, but his popularity among patrons came from his ability to create the image his sitters wished or needed to project to their subjects. He was able to capture the moral and political climate of each court, adapting his style to each client until it seemed as if his paintings acted as press releases, issued by a master of public relations.
[http://www.getty.edu/art/collection/artists/724/franz-xaver-winterhalter-german-1805-1873/]