PAINTINGS BY WAVELENGTH
examining artwork with a scientific eye
With the Sussex Colour Group, a research group at Sussex University, Lucy has extended her work on the visual diet to include examples of original artwork.
Using a monochromator, a device that emits light from a narrow portion of the spectrum, we can see the energy reflected by an image at each wavelength and use this to predict its appearance under any lighting for any animal.
The appearance at 5 points in the visible spectrum
By shining light of only one wavelength at a painting, we are able to see the intensity of the energy of that wavelength at every pixel in the scene. To understand how the appearance of an object changes under different illuminations or how it appears to different people, we need to know the
spectral distribution: how the light energy is spread across the spectrum for each point in the scene.
With this we know how much each point would stimulate the cone cells in each observers eye, be they a colourblind human, bird or tigerfish!
By setting the monochromator to shine short-wavelength light from the very edge of our visible range, you can see the paper fluoresce. This gives you a sneak-peek into the ultraviolet range of light that's invisible to us, but visible to most birds. Flourescent dye is often added to paper to boost its brightness; making parts of this image glow, while the "reference white" is dark. We use these reference surfaces when we're doing research so we don't get caught out by surprises like this!