When I research photo collections, nothing makes me happier than finding crop marks. And crop marks on contact sheets of medium format film (or larger) really are fantastic because so much of the detail of the image is clear, and the intention of the markings is usually more apparent. Crop marks make visible what is normally invisible to us … the reshaping and reimagining of the image long after the point of exposing a film emulsion to light. They can be produced by the photographer, an editor, a client – anyone with an interest in how, and in what form, the photograph will circulate. They are usually done to suit the next stage of the post-photographic process, which means that cropping is not simply an aesthetic statement (although it can be).
Crop marks are an act of foreshadowing, a projection of what might be.
Read more on Jim Opp’s personal blog: Crop Marks | Lug the camera