Fabric is folded in half and half again to make a square. Folds must be exact and wrinkles avoided. Square shown is silk chiffon. Very thin porous fabric -- cheese cloth, for example -- is preferable when, after folding, there are several layers of cloth.
The original object was scanned as a TIFF file on a Nikon Coolscan 4000 film scanner at approximately 4000 pixels on the long dimension. A 300 ppi JPEG file limited to 1024 pixels on the long dimension was then added to the CONTENTdm database.