COLOR ME OLO

Dick Pountain /Idealog 371/ 10 Jun 2025 12:15

I’ve expressed my feelings about science fiction before many, many, probably too many, times in this column. A big fan in my 1960s teens, a bout of illness in the ‘70s let me binge all the greats – Vonnegut, Ballard, LeGuin, Dick, Pohl, Bester etc – overdosing so badly that I never wanted to read sci-fi again. Looking back now as emotionally-retarded pseudo-intellectual sci-fi fans appear to be taking over the world, I think perhaps my immune system was telling me something. However this allergic reaction doesn’t apply to the closely related genre of fantasy (or gothic, or cosmic) horror. I still can cringe a little to M.P. Shiel’s ‘The Purple Cloud’, William Hope Hodgson’s ‘The House on the Borderland’, or the entire oeuvre of H.P, Lovecraft. 

One of Lovecraft’s stories, ‘The Colour Out Of Space’, struck me particularly hard. A meteorite lands in a tiny community in the New England woods, containing globules of a weird colour that isn’t in the solar spectrum: it has unpleasant effects that consume all living animals, plants and humans and turn them into grey ash. Several unsuccessful attempts have been made to film this story, hard work given that it’s not in the technicolor spectrum either: perhaps the nearest anyone has come is Alex Garland’s 2018  ‘Annihilation’ which clearly shows Lovecraftian influence and employs a digitally-produced shimmer in place of a new colour. I suppose Lovecraft’s story is a sort of parable about environmental destruction, but that’s not what explains its hold on me – I’ve always been fascinated by colour, studying its chemistry, reading up on all the various systems, appreciating great paintings and creating my own digital art as a favourite hobby.   

All of which explains my enormous excitement on reading in the Science Adviser newsletter about new research at the University of California Berkeley, which ‘creates’ a new colour that lies outside the gamut humans can perceive, but can be seen by shining a laser onto ones’ retina (don’t try this at home kids). First some background is required. You already know that our eyes, and hence also digital display devices, perceive or present colours as mixtures of the three components red (R), green (G) and blue (B). That’s because the retinas of our eyes contain three types of colour-sensitive cell called ‘cones’, sensitive to different wavelengths: long (L), medium (M) and short (S). Objects illuminated by natural sunlight stimulate L, M and S cones to different extents which gives us the experience of different colours. Red light primarily stimulates L cones and blue light S cones, but since M cones respond to the middle of the range, overlapping with both L and S, there’s no component of sunlight that stimulates M alone. 

The authors of the Berkeley paper (https://www.science.org/doi/10.1126/sciadv.adu1052) set out to investigate a new system for describing colour perception, by using a laser to illuminate retinal cells one at a time: 

“We introduce a principle, Oz, for displaying color imagery: directly controlling the human eye’s photoreceptor activity via cell-by-cell light delivery. Theoretically, novel colors are possible through bypassing the constraints set by the cone spectral sensitivities and activating M cone cells exclusively. In practice, we confirm a partial expansion of colorspace toward that theoretical ideal. Attempting to activate M cones exclusively is shown to elicit a color beyond the natural human gamut.”

Calling their new system Oz was of course a trigger for me, having cut my journalistic teeth on that notorious hippie journal where my articles were printed in every colour of the rainbow on a background of every other colour of the rainbow. But I digress. Their new colour, from stimulating M cells alone with a laser, they named ‘olo’. It can’t be reproduced in paint, ink or screen, so you’ll only ever see it sitting in a dentists’ chair with a laser strapped to your head: 

“Subjects report that olo in our prototype system appears blue-green of unprecedented saturation, when viewed relative to a neutral gray background. Subjects find that they must desaturate olo by adding white light before they can achieve a color match with the closest monochromatic light.”

Thankfully olo has not so far shown any inclination to suck the life force out of living beings and reduce them to grey ash. The best approximation is a light turquoise, a colour you might glimpse fleetingly when watching a big wave break on a rocky headland in bright sunshine. Astronomers for a while believed the whole universe, by mixing all the light together, would be a light turquoise but that turned out to be a bug in their software, and it’s now ‘cosmic latte’, a light beige (hex triplet value in standard sRGB #FFF8E7). 

[Dick Pountain wonders whether Olo could become ‘the new Pistachio’]