1. Two views of a camera obscura, 19 th century

2. LEFT: Joseph Nicéphore Niépce, View from a Window of Niépce’s House, c. 1826-27. Heliograph (photograph) on pewter, 25.8 x 29 cm (Ransom Center, University of Texas, Austin) RIGHT: reproduction, gelatin silver print and watercolor, 1952. 20.3 25.4 cm

3. Louis Jacques Mandé Daguerre, Still Life, 1837. Daguerreotype. 16.5 x 21.5 cm (Société Française de Photographie, Paris)

4. Hippolyte Bayard, Self Portrait as a Drowned Man, 1840. Direct positive photograph, 14.2 x 14 cm (Société Française de Photographie, Paris) Hippolyte Bayard, Self Portrait in the Garden, 1847. Salt print photograph, 6 ½ x 4 ¾ in. (Getty Museum, Los Angeles)

5. William Henry Fox Talbot, Window at Lacock Abbey, 1835. Negative, 2.8 x 3.6 cm (National Media Museum, Bradford, England)

6. William Henry Fox Talbot, The Open Door, plate 6 from The Pencil of Nature, 1844. Salt print from calotype negative, 5 7/8 x 6 5/8 in. (multiple locations)

7. William Henry Fox Talbot, 4 plates from The Pencil of Nature, 1844, showing different applications for the calotype process – reproducing a lithograph, a manuscript, a piece of lace, and pieces of china

8. Anna Atkins, cyanotypes from Photographs of British Algae, 1843

9. Richard Beard, Portrait of a Man, c. 1842. Daguerreotype, 2 ¼ x 1 ¾ in. (International Center of Photography, New York)

10. Southworth and Hawes, Daniel Webster, c. 1850. Daguerreotype, 8 ½ x 6 ½ in. (Metropolitan Museum) Unknown artist, c. 1840. Daguerreotype (Chester Co. Historical Society, Pennsylvania) William Kilburn, Portrait of a Man, c. 1852-55. Daguerreotype (John Hannavy collection)

11. Edouard Baldus, Roman Arch at Orange, 1851. Salted paper print from paper negative, 13 7/8 x 10 5/16 in. (Metropolitan Museum) Henri Le Secq, Large Figures on Chartres Cathedral, 1852. Salted paper print from paper negative, 13 x 11 5/16 in. (Metropolitan Museum)

12. Maxime du Camp, Abu Simbel, Egypt, 1850. Salted paper print from paper negative (Metropolitan Museum) Maxime du Camp, Temple, Nubia, Egypt, 1852. Salted paper print from paper negative (Musee d’Orsay, Paris)

13. Julia Margaret Cameron, The Angel at the Sepulchre, 1869. Albumen print from wet collodion on glass negative (The Clark) Julia Margaret Cameron, Vivien and Merlin, 1874. Albumen silver print from glass negative (Metropolitan Museum)

14. Henry P. Robinson, Fading Away, 1858. Albumen print, printed from five negatives, 24.4 x 39.3 cm (Eastman House, Rochester, NY) Oscar Rejlander, The Two Ways of Life, 1857. Albumen print, printed from 30 negatives. (Royal Photographic Society, England)

15. Eadweard Muybridge, The Horse in Motion, 1878. 12 albumen prints.

16. Charles Marville, Rue au Lard, c. 1860-70. Albumen silver print, 13 5/16 x 10 5/8 in. (The Clark) Charles Marville, Arts et Metiers, Ancien Modele, 1877. Albumen silver print, 14 ½ x 9 ½ in. (Metropolitan Museum)

17. Edgar Degas, Jules Taschereau, Edgar Degas, and Jacques-Emile Blanche, 1895. Gelatin silver print, 9 x 9 ¾ in. (The Clark)

18. ↑Peter Henry Emerson, A Rushy Shore, 1887-88. Platinum print, 7 3/16 x 11 7/16 in. (Metropolitan Museum) ←Gertrude Käsebier, Blessed Art Thou Among Women, c. 1899. Platinum print, 9 x 5 3/16 in. (Metropolitan Museum) Alfred Stieglitz, The Flatiron, 1903.→ Photogravure, 6 ¾ x 5 3/8 in. (Metropolitan Museum)

19. Kodak advertisement, Nov. 1889