If you ask a linguist what they collect when they do fieldwork on a language they will probably tell you that they make audio and video recordings. They then go on to annotate these in various ways, such as by adding information about pronunciation (transcription), meaning (translation) or word structure (morpheme-by-morpheme glossing) and sentence structure (parts of speech for words or phrases), as well as other kinds of metadata such as genre, speakers, recorders, context and so on. The theory and practice of audio and video recording, and of the different metadata types, has been much discussed in books and articles about language documentation.
There is a further kind of material which linguists collect, however, that hasn’t been at all discussed, to my knowledge, in the literature on language documentation, namely photographs. David Nathan, in a 2010 article about digital language archiving, provides the following statistics for a snapshot taken at the end of 2009 of the materials deposited in the Endangered Languages Archive at SOAS:
Audio recordings — 6,312 files, totalling 360 Gigabytes
Video recordings — 895 files, totalling 208 Gigabytes
Images — 2,221 files, totalling 28 Gigabytes
I suspect, but don’t have any hard evidence, that similar distributions might be found in other large archives like the DOBES archive at the Max Planck Institute for Psycholinguistics, Nijmegen. So why do linguists collect all these images and what do they think they might use them for? To the best of my knowledge, no-one has discussed these questions in print.
Anthropologists also take photographs during their fieldwork and there are two interesting recent posts on the Savage Minds blog that discuss the whys and wherefores of photography in the field in their discipline, one dealing with the relationship between photographs, fieldnotes and subjectivity, and the other discussing ethical issues of photography, including whether people’s faces should be shown or not. I think they would both make interesting reading for linguists as well.
Nathan, David. 2010. Archiving and language documentation. In Peter K. Austin (ed.) Language Documentation and Description, Volume 7, 172-208. London: SOAS.