Close comparison between an image of the painting in natural light and the x-ray in the centre shows how thin the upper paint layers are. Damages along the panel join are more clearly evident in x-ray than on the surface and retouching in this area is visible in the image taken in ultra violet light on the right. In x-ray it is also possible to see the cradle support and two nails holding a fragment of the panel in place.

© National Portrait Gallery, London