A member of the public tries the Horsehead at the Dead Zoo, National Museum, Dublin, November 2014

Carmella Uranga wearing the Hammerhead Helmet, Paris, July 2014

Anne working on the Yellow/Blue Helmets for the Theatre of the Mind Governor’s Island, NYC, 2017

Salammbo Connolly presents the prototype with Patrick Cavanagh at the Seeing Colour conference in Regensburg, September 2016

Study for Yellow/Blue Helmet, 2015

A scene in full colour and luminance and a simulation of the same scene in white and yellow, approximately as experienced through the Yellow/Blue Helmet filter

The Yellow/Blue Helmet at David Byrne’s Theatre of the Mind, Governors Island, NYC, 2017

Next to the light, a colour appears which we call yellow; another appears next to the darkness, which we name blue.

Theory of Colour

Johann Wolfgang von Goethe, 1810

The Yellow/Blue Helmet, a wearable version of Dr. Patrick Cavanagh’s S cone isolating technique, constructed to explore vision in pure colour, without the dark and light contrasts, and the contours, motion, and depth given by luminance. The resulting vision of the world is very challenging: motion of certain objects appears to slow or even to stop; other objects seem to suddenly move from one position to another; depth in general seems to collapse…


In 2009, Patrick Cavanagh, then director of the Vision Lab at Université Paris Descartes, first showed us an experiment he had done with yellow light and blue filters, and we have since been enthralled, if a little intimidated, by that profound and elusive experience. Difficult to describe exactly what happened. There was an unmistakable effect on the perception of movement and the sense of time passing. There was a more subtle effect on the perception of faces and other familiar things. But it was immensely difficult to figure out where these distortions were taking place: in the head, in the retina or in the real world?

It was only in 2016, when our daughter Salammbo did work experience at Patrick’s Lab, that we finally tackled a wearable version of Patrick’s experiment. That first version was presented at the “Seeing Color” conference at Regensburg University in September 2016 and we later published a scientific paper (our only one to date) on the experience, co-authored by Patrick and our daughter.

The second version was a series of six helmets that we built on Governor’s Island, New York, as part of David Byrne’s “Theatre of the Mind” (a series of rooms presenting neurological experiments). Clothing mannequins, wiring faders to LED strips, cutting gels, charging batteries, adjusting spinning displays... there was as much work on the room as on the helmets, as we struggled to render the world visible through the darkness of the deep blue filter and the haze of yellow light we were putting in front of people’s eyes. It was easy to forget that everyone who put on the helmet was seeing this for the first time and probably experiencing something like we did when we first saw Patrick’s experiment eight years ago. There was the ever present sentiment that the experience was still very imperfect; that with a little more subtility in the balance of filtered blue reality and of informationless yellow light, with a little more development in the interface between what is happening in the brain, what is happening in the eye and what is happening in the real world, with a little more clarity in the setup of the room and its moving objects, with a little better lighting, with a greater simplicity of approach...  our yellow-blue project might yet give us access to most powerful revelations. As David Byrne said, “real beauty is something that knocks you a little bit off-kilter.”


Paper published in i-Perception, May-June 2017

Section of the Yellow/Blue Helmet, 2015

Denis with David Byrne working on set of the Theatre of the Mind, Governor’s Island, NYC, 2017

The Yellow/Blue Helmet at David Byrne’s Theatre of the Mind, Governors Island, NYC, 2017