The invention of the camera in the early 19th century led to an array of lens designs intended for photography. The problems of photographic lens design, creating a lens for a task that would cover a large, flat image plane, were well known even before the invention of photography due to the development of lenses to work with the focal plane of the camera obscura.
Early photographic camera lenses (1800–1890)
The early photographic experiments of Thomas Wedgwood, Nicéphore Niépce, Henry Fox Talbot, and Louis Daguerre all used simple single-element convex lenses. These lenses were found lacking. Simple lenses could not focus an image over a large flat film plane (field curvature) and suffered from other optical aberrations. Their severe longitudinal chromatic aberration meant the light the photographers were seeing (generally yellow light) and the light to which the early photographic mediums were sensitive not converge to the same point, making it difficult to focus.
Charles Chevalier's Paris optical firm produced lenses for both Niépce and Daguerre for their experiments in photography. In 1829, Chevalier created an achromatic lens (a two-element lens made from crown glass and flint glass) to cut down on chromatic aberration for Daguerre's experiments. Chevalier reversed the lens (originally designed as a telescope objective) to produce a much flatter image plane and modified the achromat to bring the blue end of the spectrum to a sharper focus. Reversing the lens caused severe spherical aberration so a narrow aperture stop was necessary in front of the lens. On 22 June 1839, Daguerre contracted Alphonse Giroux (France) to manufacture his daguerreotype apparatus. The Giroux Le Daguerreotype camera used an almost 16-inch (40 cm) focal length reversed achromatic lens with a f/16 stop in front of it made by Chevalier to take 6½×8½ inch (about 16.5×21.5 cm) images.
Meniscus or 'landscape' lens In 1804 William Hyde Wollaston invented a positive meniscus lens for eyeglasses. In 1812 Wollaston adapted it as a lens for the camera obscura by mounting it with the concave side facing outward with an aperture stop in front of it, making the lens reasonably sharp over a wide field. Niépce began using Wollaston Meniscus in 1828. Daguerre used this lens in his experiments, but since it was a single-element lens that lacked any chromatic aberration control it was impossible to focus accurately with the blue-sensitive media in the daguerreotype process. By the end of 1839, Chevalier had created an achromatic version of the meniscus that combined field flattening and chromatic aberration control. The lens had the reverse concave flint glass side facing the subject and an f/16 aperture stop at its radius of curvature, making it reasonably sharp over a wide field of about 50°. Reversing the lens did increase chromatic aberration, but this fault could be lessened by adjusting the achromat to bring colors at the blue end of the spectrum into focus to match the blue-sensitive nature of the photographic emulsion. This design was copied by other lens makers. Because of its large flat field over a wide angle of view and its "slow" f/16 aperture (requiring twenty to thirty minutes for outdoor daguerreotype exposures), this lens came to be known as the "French landscape lens" or simply the "landscape lens".
Petzval Portrait lens
Because the Achromat Landscape lens was quite slow, the French Society for the Encouragement of National Industry offered an international prize in 1840 for a faster one. Joseph Petzval (of modern Slovakia) was a mathematics professor with no optical physics experience, but, with the aid of several human computers of the Austro-Hungarian army, he took up the challenge of producing a lens fast enough for a daguerreotype portrait. He came up with the Petzval Portrait (modern Austria) in 1840, a four-element lens consisting of a front-cemented achromat and a rear air-spaced achromat that, at f/3.6, was the first wide-aperture portrait lens. It was appropriate for one- to two-minute shaded outdoors daguerreotype exposures. With the faster collodion (wet plate) process developed in the 1850s, a camera equipped with this lens could take one- to two-minute indoor portraits. Because of national chauvinism, the Petzval did not win the prize, despite being far superior to all other entries. A 150mm Petzval lens was fitted to a conical metal Voigtländer camera taking circular daguerreotypes in 1841. The Voigtländer-Petzval was the first camera and lens specifically designed to take photographs, instead of being simply a modified artist's camera obscura. The Petzval Portrait was the dominant portrait lens for nearly a century. It had what would now be considered severe field curvature and astigmatism, but It was centrally sharp (about a 20° field of view, or 10° for critical applications), and it quickly drifted out of focus to a soft outer field, producing a pleasant halo effect around the subject. The Petzval Portrait remains popular as a projection lens where the narrow angles involved mean the field curvature is not significant. The Portrait was illegally copied by every lens maker, and Petzval had a nasty falling out with Peter Voigtländer over unpaid royalties and died an embittered old man. Although the Portrait was the first mathematically computed lens formula, trial and error would continue to dominate photographic lens design for another half century, despite well-established physical mathematics dating from 1856 (by Philipp Ludwig von Seidel [modern Germany], working for Hugo Adolph Steinheil [modern Germany]), to the detriment of lens improvement.
Overcoming optical aberrations
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