Santiago Cajal was not only a Nobel Prize winning scientist, but an enthusiastic photographer also.
When he first took up photography, people had to pose for several minutes while the photographic plate gathered enough light to produce a picture. Santiago Cajal invented a new process in which only three seconds worth of light was needed to produce a photograph. Unfortunately, he found that Thomas Edison had beaten him to it (damn you Edison).
As a result of his enthusiasm for photography, more photographs of Santiago Cajal exist than for most scientists of his era.
Pictured below: Santiago Cajal with 4/7 children.