The French photographer Charles Nègre (1820-1880) was one of the earliest practitioners of photogravure. Together with Nicéphore Nièpce, Nièpce de St. Victor, and Alphonse Poitevin, he developed the process he called héliogravure, which translated a light-sensitive photograph to a permanent ink print. Héliogravure should not to be confused with the photogravure process commonly used today, which was invented by Karl Wenzel Klic (1841-1926) and combines aquatint with a photographic negative.
In 1854, Nègre published the first reproduction of a small proto-photogravure within a page of text in the journal La Lumière. Not long after this, at the request of the architect Jean-Baptiste Lassus (1807-1857), Nègre produced a series of large architectural studies and details of Chartres cathedral, which was under renovation. Graphic Arts is fortunate to hold two of these enormous prints.
See also Françoise Heilbrun, Charles Nègre photographe 1820-1880 (Paris: Éditions des Musées nationaux, 1980). Marquand TR647 .N43 1980
Graphic Arts is fortunate to hold two of these enormous prints, light sensitive photograph printing preserve the original stature of the element in a unique way!
Does anyone know the technical differences between heliogravure and photogravure? Descriptions of the processes that I have found (after cursory research) don't distinguish them.