William Henry Fox Talbot - a scientist, mathematician, author and artist - is credited with being the inventor of photography as we know it. In mid-1834 he began to experiment with light-sensitive chemistry, and in January 1839 he announced his invention of the photogenic drawing, two weeks after Louis-Jacques Mande Daguerre's daguerreotype process debuted in France. Talbot's improved process, the calotype, was introduced in 1840. This invention, which shortened exposure times and facilitated making multiple prints from a single negative, became the basis for photography as it is practised...