At night all cats are grey
Monochrome installation, 2001

At night all cats are grey, because at night we are all colour-blind. And by day? There are people who cannot see any colours even during the day. This form of complete colour blindness is called achromatopsia. Only one in every 30 to 40 thousand persons suffer from this condition.

With these installations in two different rooms I try to simulate a world without colours in two different ways.

Human trichromatic colour vision is not a physical property of light but a physiological limitation of the eye: all colour perceptions are determined by just three physiological response systems: the electrical photo-signals produced by the red-, green- and blue-sensitive cone photoreceptor classes of the eye.
(Young-Helmholtz theory of colour vision)

Three special low-pressure sodium-vapour lamps, each of which produces monochrome light at a given single wavelength, illuminate a room in which fruits and vegetables, things commonly recognized as having a certain colour, are placed on a big table. Is colour a property of the world as it is or is it a construction of the brain?

People suffering from complete colour blindness are unable to experience any differences in hue. Their visual world is different from the world of the normal-sighted. The two worlds are not equally exclusive – the colour-normal have access to the word of the totally colour-blind: as night falls they can witness how all the different colours blend into one, and how, in moonlight, colours take on darker and lighter shades of pale. But the totally colour- blind cannot possibly access the other world in such a way. The video shows colourless situations in the world of “normal-sighted” people and has an experimental soundtrack including short parts of an interview with a colour-blind person.

Text list (video)

voice:
as it gets dark in the evening, it doesn’t seem to effect me as I’m reading. I don’t seem to see less.

text:
I imagine I see colours, I see them completely differently than normal-sighted people.

voice:
pink sky is beautiful. (Yes?) I don’t know – I imagine it is beautiful.

text:
black and white are the two extremes. green is in the middle – the sky is a bit lighter.

voice:
blue and dark blue are so close to black! so why are they still called blue?

text:
everything that’s green – grass, trees, leaves – I really want to know it.

voice:
I think the trees are beautiful when they have snow on them. They could have a little more snow than just now.

voice with the bird tree:
we had a grey cat, and it happened in the summer, when dark had set in – we were outside and I said: “there! look at the cat!” and everyone said: “where? there’s nothing there!” but really, she was there, and it was so incredible, that I could see something the others could not see.