||The locus classicus for the theory of photographic transparency is Walton 1984. Although Walton's concern is the affect of photographs, the principal influence of this paper, apart from its prompting numerous replies in response to the idea of transparency itself, was its spawning the literature on the epistemic value of photographs. Walton's paper is best understood when read in conjunction with the postscript in Walton 2008, which clarifies a number of subtle issues arguably obscured in various early responses to, and replies from, Walton. Scepticism about photography's epistemic value is vigorously defended by Roger Scruton in Scruton 1981. This paper is likewise best understood when read in conjunction with later clarificatory replies by Scruton, including Scruton 2009. Key works on the epistemic value of photography include: Cohen & Meskin 2004, Abell 2010 and Walden 2005. Key works on the affective nature of photography (in addition to Walton 1984) include: Hopkins 2012, Pettersson 2011 and Currie 1999. Edited collections include: Walden 2010 and a special issue of the Journal of Aesthetics and Art Criticism, Costello & Mciver Lopes 2012. Papers in the latter address a number of new issues in the philosophy of photography, suggesting those working in the area are beginning to move beyond the traditional issues of transparency, aesthetic scepticism and epistemic value. Notable monographs include: Maynard 1997 and Friday 2002. Three monographs in the philosophy of film that discuss photography at length are: Currie 1995, Carroll 2007 and Gaut 2010. The latter is especially notable for its theorising about the nature of digital photography.