From a set of four prints from Vignes’ Arak-El-Emir negative illustrating the progression Négre brought to the final photogravures.
Photogravure’s exquisite formal play with the granular surface of stone can be seen in one of the most beautiful photogravures Nègre ever produced: a view of Hellenistic ruins in landscape, named after the location Arak-el-Emir. The work transmits a picturesque lyricism quite different from the majority of Vignes’s negatives, which focus on views of architecture within the landscape, as another view of the same site demonstrates. The rich inky tones of the photogravures produced for the Duc de Luynes stand in direct contrast to Lemercier’s photolithographs, as well as Salzmann’s faint calotypes produced in 1863, some of which record the same sites studied by Vignes and the Duc, including Iraq El-Amir. The coincidence between Lemercier’s photolithographs after Salzmann, made by Poitevin’s process, and Nègre’s photogravures after Vignes betray yet another instance of competition between the two photomechanical producers. 
This rare book is closely connected with an important event in history of photogravure. In 1856, Honoré d’Albert, Duc de Luynes, archaeologist, scientist and connoisseur, initiated a competition in conjunction with the Société Française de Photographie (SFP) to find the best method of photomechanical reproduction. The major prize of 7,000 francs was awarded 11 years later to Alphonse Louis Poitevin for his method of photolithography. Poitevin’s method had been shortlisted for the award 1856, but declaring a winner was delayed for years because the judges considered none of the processes entered to be perfect and postponed their decision until it was clear that nothing better was imminent. Thus Poitevin became victor by default.
Meanwhile, the competition’s instigator, the Duc de Luynes, had led a geological expedition to the Dead Sea in 1864 and, upon his return, proposed to publish the pictures taken by the party’s photographer, Louis Vignes. But rather than choosing the winner of his competition to make the photomechanical reproductions, the Duc selected Charles Nègre, who had also been shortlisted for the prize. Nègre had developed a photogravure method that produced beautiful prints but was even more complicated and unwieldy in practice than Poitevin’s method- an impediment that clashed with the competition’s aim of finding the most practicable system.
Albumen prints made from Vignes’ original negatives from the expedition show the myriad of flaws that Luynes had to overcome. They were taken in harsh conditions – poorly exposed and flawed. Overcoming these issues, Nègre was able to open up the shadows and fill them with light, detail and space. “Undoubtedly the main reason the Duke chose Nègre to perform this task lay in the quality of the prints Nègre was capable of producing … for he had achieved a control over his process which resulted in prints of rich tones, fine detail, transparency and effect" . For the photogravures, Nègre created cloud formations through a combination of acid resistant varnish brushed on to the plate, powdered resin distributed over the plate’s surface, and successive submersions of the plate in an acid bath. The final results demonstrate Nègre’s technical and visual sophistication with platemaking. Not only was Négre capable of mending Vignes’ negatives, His photogravures transformed the photographs into evocative images of great poetry. Ultimately foiled by his own artistry, Négre was not awarded the Duke de Luynes’ prize … because none of the judges believed that anyone but Négre himself could produce such beautiful photo-engraved plates.
Luynes died before the work would be published, leaving the task to his son and Le Comte de Vogëé. Perhaps to save expense, they commissioned Eugene Ciceri, who had acquired fame as a lithographist around 1865, to reproduce the Sauvaire photographs lithographically. Without denying his artistic talent, it must be acknowledged that the quality of his results is inferior by far to that obtained by Negre.
While the archaeological and scientific observations within the text were groundbreaking at the time, the work is today best appreciated for its stunning atlas of photogravure plates. "To the small but vitally important field of nineteenth-century photomechanical process, Nègre brought not only technical expertise but also the eye of a master photographer and painter. Quite possibly de Luynes had expected Négre to win the prize or at least he clearly favored the photogravure print for it’s beauty, permanence and tonal nuance. Voyage d’exploration: la Mer Morte remains one of the finest photo-mechanically printed books of the era". 
For more information on this project see highlight essay: https://photogravure.com/highlights/vinges-sauvaire-placet-negre-and-the-duke/
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