Josef Max Petzval (1807-1891) designed a photographic-lens and invented the first rapid portrait lens. He gained technical advice from the Viennese optician Peter Voigtlander who also made the first of Petzval's portrait lenses. This became the basic design and was in use for many years. The two men later parted company, with Voigtlander producing a lens in competition with Petzval. Following this and also a burglary, he left optics and moved to acoustics.
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