In his book Camera Lucida, Roland Barthes identifies two main factors in a photographic image: studium and punctum. Studium is the element that creates interest in a photographic image. Punctum is an object or image that jumps out at the viewer within a photograph.
Studium shows the intention of the photographer. Journalistic photographs are good examples of studium. Studium adds interest, but in the order of liking, not loving. Punctum often accompanies studium, but it also disturbs it, creating an ‘element which rises from the scene’ and compels your attention. Punctum may be a discovered detail that attracts you to an image. According to Barthes, punctum's "mere presence changes my reading, that I am looking at a new photograph, marked in my eyes with a higher value." Punctum changes the ‘like’ of studium to the love of an image and requires an accidental quality about it to be most effective. It is very personal and often different for everyone, but shares the common experience that it moves the viewer.
After trying to figure out what fine art photography is (besides a marketing term), I am more convinced then ever that Barthes' Punctum differentiates great photographs from the mundane. Size, both large and small, as well as aspect ratio, contribute to the punctum of a printed image and, for me, seem to be lacking in online viewing.
Of this I am certain, a photograph must first move the artist before it will move the viewer. After punctum, the rest is marketing juju.
See ya around,