Toronto. Did you ever wonder how Chevalier managed to make the first camera for Daguerre complete with a lens before 1839 ? The lens had been designed a quarter century earlier c1812 by the Englishman Wollaston as a landscape lens for the then popular Camera Obscura. It was a simple meniscus design with the concave side facing the scene. The primitive lens was about f/15 in today’s terms.
The meniscus design resulted in a flatter field of view than any previously used Camera Obscura lenses. However; the meniscus when used on a Daguerreotype camera was not great as its chromatic aberration was too high (and too variable with focusing distance). For example, when the human eye saw warmer colours were in focus on a ground glass, the resulting image on the daguerreotype plate was out of focus (the medium was more sensitive to the cooler blue colours). By 1839, Chevalier had solved the chromatic aberration problem by adding a second element cemented to the first allowing the focus on the ground glass to match the focus on the silvered plate.
To read more, pick up a copy of Rudolf Kingslake’s “A History of the Photographic Lens“, (1989) or Josef Eder‘s epic “History of Photography” (1932, 4th edition) translated by Edward Epstein and published in 1945 by Columbia University with the Dover reprint in 1978.
NB. The title is a line from Montrealer Leonard Cohen’s song/poem “Anthem“. I have enjoyed his music and poems for over a half century now. This version is from his last world tour and was recorded in London, England.