Cartoon Bust — Orchestra Conductor, Iridescent Finish, Vienna

He conducted the same orchestra for twenty-two seasons. The house wanted the bust in the foyer, which is a space with a great deal of glass and a great deal of chandelier, and they were worried about one thing: that a sculpture in there would look like luggage.

The proposal

An iridescent finish. Colour-shifting paint over a dark base, so that the piece has no fixed colour at all and instead takes its colour from wherever the viewer happens to be standing. In a foyer with chandeliers and moving people, that means the bust is never the same twice.

Designing for a moving surface

Colour-shift pigment works on curvature, so the geometry has to be chosen for it. Flat panels read dead; tight curves read as stripes of colour. We kept the bust deliberately rounded — a large softened head, a smoothly bulging shoulder line, corners radiused away — and used the baton, held horizontally across the chest, as the one hard straight element. It reads as a black line until the viewer moves, at which point a gold flare runs along its length.

The face is the constraint. Colour-shift on a face is a distraction, so the head is finished in a near-solid dark base coat with the flip pigment held back to the outer edges of the skull and the jaw. The likeness lives in a calm dark area in the middle of a shifting object.

Build and finish

Fibreglass over a steel core, blocked to a much finer tolerance than usual because a colour-shift coat shows every defect twice. Six coats of base, the interference layer, then two clear coats. The whole surface is under the clear, so the baton can be handled without damage.

In the foyer

It stands to the side of the main doors, at 1.8 m, on a black steel plinth. The house reports that audiences arriving for the evening concert see it as green and leaving see it as magenta, because the light coming through the glass changes. Nobody planned that and it is the best thing about the piece.