Starry night of the soul: Study of Van Gogh paintings reveals his state of mind
Unmasking the original colours of two Van Gogh paintings have shown how the changing state of the artist's tortured mind influenced his work.
Both are of the same subject, Vincent van Gogh's bedroom at 2, Place Lamartine, Arles, Bouches-du-Rhone in France.
Today the two versions of Bedroom At Arles, painted a year apart, look much the same.
But peel away the surface using a technique called x-ray fluorescence spectrometry and striking differences emerge.
In the first painting, completed in 1888, the room was originally composed in cheerful, luminous colours - pale violet, yellow, scarlet, lilac and light green.
The second version, painted after Van Gogh had fallen out with fellow artist Paul Gauguin and cut off a piece of his own ear, was darker and more sombre, so that the shade of violet chosen was almost blue.
It is housed at the Art Institute of Chicago, where a major new exhibition is bringing together both paintings together with a smaller third copy also completed by the artist.
Dr Francesca Casadio, an art conservation scientist at the Institute, whose team conducted the analysis, said: "Van Gogh had a room ready for Paul Gauguin and he had been working non-stop for weeks painting all the paintings for the walls, and when he was finished he slept for two days.
"So the original painting shows he was satisfied. With the original painting he wanted it to look more like a Japanese print, but with the Chicago version he was in a more sombre mood. He was in a different place by then and the new visualisation reveals that .. by that stage the colours were much more subdued.
"He had been in hospital, he had cut off a piece of his ear and had fought with Paul Gauguin. They were painted a year apart between 1888 and 1889 when everything had changed. And it is reflected in the work."
Over time natural chemical processes meant that the colours in the paintings altered in subtle ways, causing them to appear much more alike.
Dr Casadio outlined the findings at the annual meeting of the American Association for the Advancement of Science (AAAS), taking place in Washington DC.
Describing the first painting in a letter to his brother, Van Gogh said: "I have painted the walls pale violet. The ground with checked material. The wooden bed and the chairs, yellow like fresh butter; the sheet and the pillows, lemon light green. The bedspread, scarlet coloured. The window, green. The washbasin, orangey; the tank, blue. The doors, lilac. And, that is all."
The researchers were able to show conclusively which painting came first.
Dr Casadio said: "We knew that the original was water damaged while Van Gogh's letters tell us that with the second painting he had some difficult with getting the layers of paint to adhere together. So we were able to use the x-ray technology to search for evidence of damage and we saw the water damage in the first painting and saw that there was evidence of adhesion problems in the second.
"So we have used scientific evidence coupled with his letters to solve this problem."