For every work of art on paper featured in an upcoming exhibition, our lab in conservation examines it to determine its condition and whether any treatment is needed. So when we received a woodblock print from Yoshitoshi’s Demons, an installation of works from one of Japan’s top print artists of the Meiji era (opening at LACMA tomorrow), we noticed a disfiguring gray patina over some of the image’s red areas. We immediately set to work trying to figure out whether the gray was intentional or a form of degradation.