British polymath known for inventing the actinometer. He is regarded as one of the founders of photography and made several improvements to the processes including the inventing of cyanotype.
On 9th September 1839, Herschel made a photograph on glass which still exists. He is also credited to having coined the term photography, though the word in the French spelling (photographie) had earlier been used by Hércules Florence. Herschel was also the first to use the words positive and negative in photography.