Photographs of Stars, Star-Clusters and Nebulae: Together with Information Concerning the Instruments and the Methods Employed in the Pursuit of Celestial Photography

A geologist and fellow of the Royal Astronomical Society, Isaac Roberts (1829–1904) made significant contributions to the photography of star-clusters and nebulae. By championing reflecting rather than refracting telescopes, Roberts was able to perceive previously unnoticed star-clusters, and was the first to identify the spiral shape of the Great Andromeda Nebula. Roberts' use of a telescope for photographing stars, and a long exposure time, provided greater definition of stellar phenomena...