Is that the image on the tilma, or is it a painting?
One of the extraordinary qualities of the image is its sharp edges, despite the coarse weave of the tilma. Much of what appears in the photograph has been painted in -- e.g., the angel, the stars. In fact, as far as I know, infrared studies have shown that only the underlying image of Mary is original. It has not yet been determined what the medium is, but it doesn't saturate the tilma; rather, it floats above it like a photographic emulsion.