It's been lying for a century in a forgotten corner of the Bredius Museum in The Netherlands, but now experts believe The Raising of the Cross is the work of Dutch master Rembrandt.
The artwork from the 1640s was first bought by the museum's original curator Abraham Bredius in 1921. He too was convinced the sketch was an original Rembrandt, but over the years art experts dismissed the work as a "crude imitation" by one of Rembrandt's followers.
New scientific techniques
Johanneke Verhave restored the sketch and using new scientific techniques became convinced Rembrandt - the painter known for famous works like The Night Watch - was the artist.
"We had an infrared reflectography made and with that you can see a possible underdrawing or maybe changes in the painting," she explains. "In fact there are several changes in the painting, which means that the painter was changing his mind while he was working. He wasn't copying another painting, which is important because looking at this painting you could say maybe it's just a copy of Rembrandt. No, this is really an artistic product."
Devil is in the detail
Verhave studied The Raising of the Cross with Jeroen Giltaij, former chief curator of old paintings at Rotterdam's Boijmans Van Beuningen Museum. He agrees the painting is an original Rembrandt and the proof is in the brush strokes which he describes as "brilliant".
"When I was looking at it, I thought: I think Bredius was right, you have to realise that it's an oil sketch so then you have to look at it in a certain way," he says. "I think it's really by Rembrandt but you will not recognise the refined Rembrandt, but when you study it very carefully I discovered there is even a self-portrait in the painting."
The sketch also harked back to a 1633 Rembrandt painting also entitled The Raising of the Cross which now hangs in the Alte Pinakothek art museum in Munich.