Uploaded X-ray image of Vincent van Gogh's *Portrait of an Old Man with a Beard* (1885), sourced from ResearchGate [fig2_295904195].
This X-ray will be used as Dataset Set 2 for torque pattern comparison with *The Tree Oil Painting*.
Notable for its layered brushstroke structure, visible torque arcs, and historical pigment density, the image provides a verified reference point for cross-canvas stroke analysis.
File name preserved as per original citation.