According to researchers at Denmark’s State Museum of Art (SMK) and the Centre for Art Technological Studies and Conservation (CATS), Christen Købke did not intend to portray View of Lake Sortedam (1838) as a sunset.

Experts have long said the landscape depicts a purple sunset over the Copenhagen Lakes, in keeping with other paintings from this romantic period of his oeuvre. However, the results of recent technical analysis havet shown that the artist actually painted a bright summer day, the colors having changed dramatically in the years since it was painted.

SMK’s head conservator Troels Filtenborg explained that the painting’s original colors at the canvas’ outer edge were protected by the heavy wooden frame. “We noticed that the colors along the edges near the frame were different from the colors in the rest of the painting,” he said. “And the difference became even more noticeable when the painting was taken out of its frame entirely.”

Based on the observation, Filtenborg and his team discovered that a chemical reaction within the red, white, and blue pigments caused the lake to change to a purple and red hue and that 176 years of light exposure have caused the sky to fade considerably.

According to Kasper Monrad, head researcher at the SMK, the discovery changes the way that Købke’s oeuvre should be viewed and may even lead to the painter’s art historical stock being reevaluated.