COPENHAGEN.- The painter Christen Købke’s famous painting of the view of Lake Sortedam in Copenhagen has long been believed to be a painting of a romantic sunset – but this is not, in fact, the case. The startling discovery was made thanks to new analyses carried out by scientists at CATS and conservators at the SMK.

It has long been perceived as a beautiful sunset where the reddish glow of the evening sun creates a purple sheen on the waters of the Sortedam lake. In fact, however, Christen Købke’s classic painting View of Sortedam Lake is a depiction of a sunny summer’s day whose original colours have changed since it was painted back in 1838.

”We noticed that the colours along the edges near the frame were different from the colours in the rest of the painting. And the difference became even more noticeable when the painting was taken out of its frame entirely,” explains Troels Filtenborg, who is head conservator of painting at the SMK.

Together with fellow conservators Anna Vila and Jørgen Wadum he has carried out a number of scientific analyses of the work at the Centre for Art Technological Studies and Conservation (CATS). Here it was established that Købke’s work had indeed changed its appearance over time.

A chemical reaction in “Prussian blue” causes colour changes
The colours have changed due to a chemical reaction in the blue pigment, which is known as Prussian blue. The colour changes have been exacerbated by 176 years of exposure to light.

The sky has become paler and lighter. And the lake, which was painted using a mixture of red, blue, and white pigments, was originally a bluish grey. Now, however, it has taken on a reddish, purplish hue. The frame in which the work is set has protected the original colours out at the very edge – and this difference in colour piqued the conservator’s curiosity.

Changes our perception of the painting
Kasper Monrad, senior researcher at the SMK, states that this new discovery completely changes how we should look at this painting. Up until this point the work was believed to be a romantic sunset scene. In the mid-1830s Købke painted many romantic artworks – and this work has been regarded as part of that group. In light of the new knowledge – that the scene actually shows a bright summer’s day – the work must be regarded as far less romantic in scope.