| Europe • Austria | First lens designed specifically for photographic purposes by Hungarian-born Józeph Petzval (1807-1891). |
Europe • Great Britain
| John Herschel successfully fixes sensitized paper using his 1819 discovery of hyposulphite of soda dissolved in silver salts still used today called hypo. |
North America • USA
| John William Draper (1811-1882) takes the first Daguerrian plate showing the solar spectrum. |
| North America • USA | Alexander Simon Wolcott and John Johnson open the world's first Daguerreian Parlor in New York. (March 1840) |
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