It is an optical illusion to rival the famous blue or gold dress that flummoxed the world … why do pictures of a new piece of public sculpture in England all look as if they have been clumsily photoshopped?
The giant seventy-five-metre-long Blade was installed in the centre of the city of Hull earlier this year as part of its UK city of culture celebrations. However, the 25-tonne wind turbine blade immediately raised eyebrows when people started to photograph it. As this snap shows, many images of the sculpture look like really awful fakes as if the Blade had been added to the image afterwards.
Now vision science researchers from the University of Lincoln have finally solved the conundrum of the photoshop effect. They found the visual illusion is being cause by the way light is reflecting off the blade and playing havoc with people’s pre-conceived ideas of how it is lit. Effectively, the shape of the Blade is being altered to the human eye and causing confusion.
Daylight hitting it from above produced shading which created an illusion that the blade was a cylinder and that it was being lit from the side rather than above. This, their study showed, reinforced the illusion that the blade is out of place and that images of it have been altered. Professor George Mather said: “I saw pictures of the installation in the media, and at first sight the photographs seemed to be clumsy fakes. Something else seemed to be at work too, at least to my eyes as a vision scientist.
“The blade appeared to be a cylindrical object, strangely out of keeping with the local environment, lit differently, as though it was superimposed on the scene digitally, but it really was there.” The Blade was made by Siemens and is part of the Look Up exhibition, a programme of temporary artworks in Hull’s public spaces to coincide with the city’s year as UK City of Culture.