X-radiograph(s) of "St. John's Altar" 

Curator: At first glance, it appears almost like an abstract painting, stark and monochromatic. A network of lines creates a sense of depth and texture. Editor: This is an X-radiograph of the "St. John's Altar," after Rogier van der Weyden. It's a glimpse behind the surface, revealing the hidden structure of the painting. Curator: Fascinating. The visible underdrawing provides insight into the artist’s creative process, the evolution of forms and composition, offering a rare look beneath the established surface. Editor: Absolutely, and these radiographs offer a window into conservation efforts. They allow us to assess the painting's condition, to detect any damage or past restorations, thus informing its preservation for future generations. Curator: It serves as a striking reminder that every artwork has a history beyond what we see. Editor: Yes, and that the act of looking at art is not just about aesthetic appreciation, but also about understanding the cultural and historical forces that shape it.