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For decades, art historians have wondered what made Claude Monet and Edgar Degas evolve from landmark impressionist painters to what some consider to be shadows of their former selves. Now, a Stanford University ophthalmologist has used the Gaussian filter and other Photoshop wonders to replicate how the artists saw the world later in life.
The verdict: The painters couldn't paint the same way anymore because they couldn't see the same way.
"It's no secret that both Degas and Monet had failing vision. What's never been clear is what did that mean for them," said Dr. Michael Marmor, who studies how the brain processes sight. With the help of Photoshop, "we realize how this limitation may have influenced their style."
The findings raise doubt about the prevalent theory that later in life, the painters were influenced by more modern, expressionist artists like Van Gogh and Seurat, who used darker, heavier lines and sharply contrasting colors.
Monet and Degas are both known as masters of the French impressionism movement, which is characterized by short brush strokes, pastel colors and indistinct outlines that the eye blends from a distance.
Both artists suffered from eye disease in their later years. Monet had cataracts while Degas, famous for his paintings and sculptures of ballet dancers, likely suffered from macular degeneration, Marmor said.
Degas' brushwork seemed less refined closer to his death in 1917. The changes could have been a natural evolution of his painting style or the result of other aspects of aging. So Marmor tested whether vision played a role by using Photoshop to re-create what the artist might have seen.
He manipulated three paintings of nude women bathing in order to see them as the artist would have with 20/50, 20/100 or 20/300 vision. Marmor determined how much blur to use by applying filters to an eye chart and observing which level of blur most replicated a particular level of vision.
While the two later paintings (After the Bath, Woman Drying Herself and Woman Drying Herself) look rough in their original form, the blurring effect eliminates the coarseness. "If you look at these same late works as they appeared to him, they don't appear so crude," Marmor said. "He may not have been able to realize or understand how they looked to those with normal sight."
Monet preferred to paint nature and buildings. Cataracts, which he suffered from between 1912 and 1922, when they were surgically removed, disrupt color perception and visual acuity.
According to Marmor, Monet's work began to show a yellowish cast as his cataracts developed. To reveal how Monet saw the world, Marmor darkened images using Photoshop and reduced the levels of blue to replicate a yellowing effect. He also used blurring filters.
The results suggest that Monet's vision corrupted his ability to see colors correctly. This -- and not a desire to reflect the growing expressionist style of painting -- may explain the abstract nature of Monet's later work.
Marmot published his findings in the December issue of the Archives of Ophthalmology.
Bradley Fratello, an art historian and assistant professor at St. Louis Community College, said he's unconvinced that eyesight influenced the artists more than contemporary artists like Van Gogh and Seurat.
In the paintings of women bathing, Degas demonstrates his ability to draw fine lines in some portions of the works, Fratello said.
"If you can't make refined lines because you can't see, then you can't 'choose' to make them some places and not others, can you?"
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