A drum of machined aluminium cut into dozens of fine radial fins, with the source hidden dead centre. Light can only leave between the blades, which fires it out in a full sunburst, a fan of hard-edged rays that reaches a metre or more across the plaster in every direction. The fitting itself stays dark and compact; the wall becomes the light. It is the sort of effect that only works on a plain surface, and on a plain surface it is remarkable.
