A property used to describe and classify images according to the following controlled vocabulary:

• Dissertation Figure: A drawing included in Mark Lehner's 1991 Archaeology of an Image: The Great Sphinx of Giza. Ph.D. dissertation, Dept. of Near Eastern Languages and Civilizations, Yale University.
• Dissertation Plate: A photograph included in Mark Lehner's 1991 Archaeology of an Image: The Great Sphinx of Giza. Ph.D. dissertation, Dept. of Near Eastern Languages and Civilizations, Yale University.
• Field Drawing: A drawing done in pencil in the field, at the Sphinx, usually measured from points on the Sphinx Project grid.
• Inked Drawing: A drawing drafted in ink, usually traced from a field drawing.
• Master Drawing: Plan and elevation drawings of the whole Sphinx, the whole of the temples to the east, or the whole site. Plans composed of separate field drawings. Elevations done by photogrammetry.
• Working Drawing: Intermediate drawing between field drawing and inked final drawing or master drawing, to help compose the inked or master drawing, for example plotting survey points for features on the Sphinx head by triangulating angles measured by theodoloite from the Sphinx Project survey grid.
• Photograph: Photographs taken during and after the Sphinx Project. Includes black and white photographs and color slides.