Photograph by William Henry Fox Talbot (1800-1877), showing two men wearing tailcoats, hat in hand, greeting one another. Talbot invented the first negative/positive process for producing photographs between 1835 and 1839. This meant that for the first time any number of prints could be made from the same shot by transferring the negative image on to special paper to make a positive print. Talbot's process for achieving this is known as the calotype, or Talbotype, process.
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