Leaf casting may be one of the most important tools for a book and paper conservator. Most essential for good results is the determination of how much pulp is needed for specific casts; this depends on the thickness and size of the object. Uneven holes, ragged edges, and other phenomena make an accurate manual calculation unsatisfactory. A system is described that does this calculation using a video camera, a digitizer that converts the video image into a digital image, and a personal computer.