It’s the application made by the Veronica to clean Jesus’ Face way to the Calvary and stamps the hurting Face of Jesus, covered by blood that comes out from the wound in a “3” shape from the forehead beneath the crown of thorns. It’s perceivable the silhouette of a hand interposed between the Face and the Sudarium when retiring the blood near the right eye lachrymal, which prevented the Sudarium to pick up the blood from the right cheek bone; this hand is the same size and proportion as the stamped on the Shroud. The hand presents its palm not its back, which indicates it wasn’t to clean himself, but that Jesus was covering himself from some strokes, and stop them from stringing or not to the Sudarium.

Rollover & clic.