Ingres seem to have adapted elements of the approach and technique of Hans Holbein 's 1527 Portrait of William Warham , now in the Louvre . Neither artist placed much emphasis on colour , preferring dark or cool tones . The Warham portrait seem to have informed the indicators of Bertin 's aging and the emphasis on his fingers . Jacques @-@ Louis David also explored hyper @-@ realism in his depictions of Cooper Penrose ( 1802 ) and Emmanuel Joseph Sieyès ( 1817 ) . In the later painting , David show tiny glints of light reflecting on the sitter 's chair and painstakingly details " every wayward curl of [ Sieyès ' ] closely cropped auburn hair . "