A radiograph is read by subtraction. Bone stops the beam and stays pale; air passes it and goes black; everything between is a continuous gradient of developed silver. The film base carries a blue anthracene dye, so the whole image sits cold — that tint is what makes a radiograph identifiable across a room.

Off the viewbox the film goes back into an 11 pt manila jacket, tabbed and pocketed, filed by accession number. This system runs on both surfaces: the lit blue-black film for content, the tan kraft jacket for metadata. Square corners, typewriter numerals, opaque lead markers in the corners.