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History of photographic lens design
The invention of the camera in the early 19th century has led to a large 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〔(Rudolf Kingslake, A history of the photographic lens, page 23 )〕 due to the development of lenses to work with the focal plane of the camera obscura, a device for projecting images used as a novelty and an artist's drawing aid that had been around for hundreds of years. Since the invention of photography many types of lenses have been tried. The succession of designs was never uniform since an older design that performed a task the photographer needed (such as working better portrait versus landscape, working at the wavelength of light the film collected, etc.) would still be used in unison with newer designs. Even today the job the lens needs to do, the laws of physics, the limits of engineering, as well as the practical considerations of size, weight and cost, means there are many designs available.
==Early photographic camera lenses==
The early photographic experiments of Thomas Wedgwood, Nicéphore Niépce, Henry Fox Talbot, and Louis Daguerre all used simple single element convex lenses.〔(Michael R. Peres, Focal encyclopedia of photography: digital imaging, theory and applications, page 55 )〕 These lenses were quickly found lacking. Simple lenses could not focus an image over a large flat film plane (Field curvature) and suffered from other optical aberrations. The severe longitudinal chromatic aberration of these simple lenses meant the light the photographers were seeing (generally yellow light) and the light the early photographic mediums were sensitive to did not converge to the same point, making it difficult to focus the image.
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 it needed a narrow aperture stop in front of the lens to control this. On 22 June 1839, Daguerre contracted Alphonse Giroux (France) to manufacture his official daguerreotype apparatus, including the world’s first production photographic camera. 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.〔Todd Gustavson, ''Camera: A History of Photography From Daguerreotype to Digital.'' New York, NY: Sterling Innovation/Sterling Publishing Co., Inc., 2009. ISBN 978-1-4027-5656-6. pp 8-9.〕〔Colin Harding, ''Classic Cameras.'' Lewes, East Sussex, UK: Photographers’ Institute Press, 2009. ISBN 978-1-86108-529-0. pp 18-19.〕
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