Written by: Cehao Yu

The 42nd edition of the European Conference on Visual Perception assembled perception and vision-related research conducted in many disciplines (including psychology, neurosciences, biology, computer vision, computer graphics, light and lighting technology and sports and rehabilitation). The conference was held in Leuven, a town with a rich history and architectural heritage. My optical nerves have been fully stimulated with a glance at the night view with the deep blue dusk sky as a backdrop, see the photograph. It shows how the warm ambient light, the highlights from the window reveals, and the sparkles from the vintage light sources blend together in a harmonious way. This is how an ideal vision conference should start.

As a design engineer in the field of light and lighting, I have always believed that applications should start from addressing fundamental questions. My current academic work focuses on the exploration of chromatic light fields effects from physical and perceptual aspects. I had been selected to present my current research outcomes in the form of an oral talk. Although my rehearsals went well behind the stage, the live presentation was somewhat dramatic due to unforeseen circumstances beyond my control. Somebody in the audience fainted in the middle of my talk. Everybody was shocked, but the chairman took immediate action to arrange an ambulance and medical care. Luckily, I have managed to use some time for a re-start after a short pause and continued my presentation. The talk overall went well and the short discussions with other researchers in this field are of great value. My quest to understand more and dive deeper into this topic is only intensified.

The conference organised various platforms to encourage positive scientific engagement, i.e. poster presentations, oral talks, symposia and keynote lectures, as well as many moments to network and meet the other participants (e.g. a conference dinner and an environment that facilitated joint lunches and dinners). The opportunities to connect with other researchers and the academic community in a global context were of great value for getting acquainted with different perspectives within this vision science community, and dialogues to stimulate innovative ideas.

As Perceptual Intelligence Lab we also presented a demo at the Phenomenal Vision Night, namely ‘colour effects in natural light fields’. We showed that cast shadows can be coloured due to lighting from a source with a much lower luminance and more diffuse spatial distribution than the shadow-casting source. This happens for instance on a sunny day with a blue sky, causing shadows to be blueish. We demonstrated this effect both subtly and theatrically. General public as well as scientists were attracted by the strong visual effects in such a simple setup. The theory and effects can also be observed in nature. We demonstrated the effects more dramatically. Hopefully, people who have joined this demo will find it fun to observe and recognise the effects in nature. As the famous football player Johan Cruyff once said “Je gaat het pas zien als je het doorhebt,” that is, “You will only see it once you understand it”.