The document outlines major technological milestones in photography from 1851 to 2005. It discusses the introduction of wet plate collodion in 1851, the panoramic camera in the late 1850s, the popularity of stereoscopes in 1861, the replacement of wet plate collodion with dry plate collodion in 1871, the invention of rolled photographic film by George Eastman in 1888, the introduction of 35mm color film in 1935, the use of satellite phones by photojournalists in 1995, and the development of hybrid film/video DSLR cameras in 2005. Each milestone represented an important advancement that changed the practice of photography.