[The FSA photographer] must be a good deal of a social scientist, with some theoretical and much practical grounding; he is the social investigator with a camera as his note-book; he must be a first-rate reporter - not of spot news - but of the major currents of our time as they manifest themselves pictorially in any one location. He must be able to distinguish between biased information and fact; he must have a wealth of knowledge of a variety of subjects - from rural architecture to tractor construction; and he must be capable with pencil and note-book to almost the same degree as with lens and shutter.
To do this kind of job the photographer has to be more than an artist - more than an adequate mechanic. He must be something of a sociologist, something of an economist; he must be a good deal of a wangler, equally at home with a hostess or a farmer’s wife; he must have a healthy nose for news coupled with a thorough scepticism of biased information; and more than anything else, he must have a basic understanding for the meaning of his story.
The Farm Security Administration's brief for photographers, from the 1930s. More on this - plus crocodiles and hole-punches - in the latest email.