Bringing back the colors

The battlements on top of the tower of Montmajour are hardly visible anymore, and the grass and stones at the base of the castle are seriously faded. “Luckily, we also have a reproduction of this drawing from Vincent van Gogh [which he made in 1888, ed.],” says Dr Jan van der Lubbe, as he pokes around in his papers. Spread out on the desk of the image processing expert are heaps of pictures of drawings by the great Dutch artist. “Here, you see? This reproduction was made in 1928. It’s very valuable, since the dyes of this reproduction haven’t degraded yet.”

Together with colleagues from the Tilburg University and the Van Gogh Museum, Van der Lubbe received a grant worth some 750,000 euros from the Netherlands Organisation for Scientific Research to develop data mining and image processing tools that must help digitally reconstruct the way Van Gogh’s paintings and drawings looked in the old days. Two PhD students will be appointed, one at each university. The one at TU Delft will focus on the drawings, while his colleague in Tilburg will study the paintings.

In addition to reproductions, the researchers hope to retrieve interesting information from the drawings’ edges. While the exposed image underwent various degrees of fading, ink on the edges sometimes retains its old color (often bright purple, a color Van Gogh used a lot) if it was hidden behind a mount.

In some cases however there is hardly any information. The challenge here is to reconstruct the drawing on the basis of similar, well-kept drawings. Also, there are letters from Vincent written in purple ink in the same week when he made purple drawings. Since the letters were kept in the dark, they did not change color, and this information will also be used.

Van der Lubbe and his colleagues from Tilburg have collaborated before on other art-related projects. Several years ago they developed software that distinguish fake Van Gogh’s and other forged paintings from the real thing by analysing numerous traits, such as brushstrokes and colors. When this project was completed, the researchers teamed up to analyse the paper the painters used.

Studenten ‘international business and management studies’ hadden bij de examencommissie geklaagd dat er was afgekeken tijdens twee deeltentamens budgeting. Sommige studenten zouden zelfs met hun mobieltjes foto’s van de toets hebben doorgestuurd naar medestudenten die deze later op de dag moesten maken, meldt hogeschoolblad Punt.

Omdat de studenten niet op heterdaad zijn betrapt, moet iedereen de tentamens opnieuw maken. In een brief aan de studenten wijst directeur Nies Rijnders erop dat spieken niet te tolereren valt. Het zou de betrouwbaarheid van het Avans-diploma in gevaar kunnen brengen, vreest hij.

Om problemen in de toekomst te voorkomen heeft Rijnders maatregelen genomen. Voortaan worden tentamens apart ingeroosterd in grotere lokalen – waar de tafels verder uit elkaar staan – met meer surveillanten. Ook zullen er meerdere tentamenversies worden gemaakt.

De afgelopen maanden raakte een aantal hogescholen in opspraak vanwege frauderende studenten, waarna er in de media hardop getwijfeld werd aan de waarde van het hbo-diploma.