History of Photography:
Sir John Frederick William Herschel, (1792-1871) was an inventor and Pioneer of experimental photography, English mathematician, Astronomer and Chemist. The use of Julian day system in astronomy was introduced by him. He was invent the Cyanotype process in Photography, investigation of Color blindness, Power of Ultra violet rays and invent some new methods and chemicals for Photographic process.
He coined the word called “Photography” in 1839 after Hercules Florence and applied the terms positive and negative to photography.