The National Trust has authenticated a Rembrandt that was once thought to be by a student or follower, according to the Times:

The painting underwent a thorough technical examination, said Christine Slottvedd Kimbriel, paintings conservator at the Hamilton Kerr Institute, which included a series of close visual examinations “under magnification, infrared reflectography, x-radiography, raking light photography and pigment and medium analysis.

”Careful cleaning removed layers of aged and yellowed varnish, revealing the original colors and painting style underneath, she added. “What was revealed was a true depth of color, much more detail and a three-dimensional appearance to the fabric in Rembrandt’s cloak which had previously been obscured and detracted from the quality of the work in the eyes of the Rembrandt Research Project,” she said.

Specialists also closely examined the artist’s signature, considered contentious in previous assessments because the style reflected Rembrandt’s signature from a much later period in his career, not when the portrait was painted. “But, the cross-section analyst left no reason to doubt that the inscription was added at the time of execution of the painting,” Ms. Kimbriel said.Furthermore, X-ray photography and infrafred reflectography, commonly used in art conservation to reveal underlying layers like underdrawings, showed various alterations in the composition that were typical of Rembrandt. For example, changes to the outline of the figure were carried out at a late stage and without much care to match the surrounding paint, Ms. Kimbriel said, as well as the outline of a hand that had been previously included in the composition but later removed.

Turns Out That Guy in the Painting Really Is Rembrandt, Analysts Say (NYTimes.com)