Four years ago, I bought a big lens engraved as “Photographe a Verres Combines Invente par CHARLES CHEVALIER Ingenieur” from a major lens shop in Germany. I strobgly believed the lens is the Chevalier’s Verres Combines lens which won a conpetition of lens development against Petzval in March 1842. I didn’t check the lend design by opening the lens because it’s engraved as “Verres Combines”.
Kingalake wrote in his book “A History of the Photographic Lens”:
I. CERVALIER’S PHOTOGRAPHE
Chevalier, always the empiricist, began experimenting with various combinations of lenses that he had available on the shelf and discovered that by adding another between the stop and the lens of his landscape objective, he could raise the apature to f/6, about six times faster than his original system. Furthermore, he found that he could use different added lenses and even turn the system around in the camera to adapt it for various uses, landscapes, portraits, and so on (Fig. 3.1). He called it the Photographe a Verres Combines a Foyer Veriable, the word photographe reffering to the lens was not to the picture made with it.
Unfortunately, Chevalier’s new lens was not all that good, and although it was manufactured for some twenty years by Chevalier and his son, it could in no way compete with the Petzval Portrait lens.
I made some sample pictures using the “Photographe a Verres Combines” lens. I was happy with the soft image produced by the historical lens.
Last week, one of my friend showed me a sample picture of Chevalier’s Verres Combines” lens. It was very different. This encouraged me to check the lens again.
Ass soon as I opened the lens, I realized it’s a Petzval lens. The soft image was because the front lens element was reversed. After I assembled the lens as original Petzval design, it turned to a sharp Petzval lens. I appologize all readers that my messages of this lens were all wrong.
I’ll test lens as Petzval lens again using Deardorff 8×10.