Artist: James Turrell
Location: Gulval, Cornwall
Client: Tremenheere Sculpture Gardens
Completed: June 2015

Designed by renowned artist James Turrell, 'Tewlwolow Kernow' ('Twilight Cornwall') is an installation at one of the highest points of Tremenheere Sculpture Gardens in Gulval, near Penzance. It is one of over eighty Skyspaces that exist worldwide, each consisting of a plain viewing room with an aperture in the ceiling, prompting the viewer to contemplate their perception of light as it changes above them.

The Skyspace at Tremenheere is approached through a narrow tunnel in the base of the hill, which amplifies the feeling of openness as the visitor emerges into the white ellipsoid which has an oval aperture that opens up to the sky. As one of only two ellipsoid Skyspaces, its curved walls mark a departure from the usual vertical walls of Turrell's other Skyspaces, adding a new dimension to the experience.

The brief for this project was to create a lighting scheme for Tewlwolow Kernow that would complement the experience of the visitor without distracting from the contemplative atmosphere of the Skyspace. I was approached to work on this complex project because of my technical skills as an electrician, as well as my skills as a designer.

Vital to the success of the lighting scheme was placement. After discussing the scheme with Dr. Armstrong, the owner of Tremenheere,  I installed concealed LED strip around the edge of the space, angled to throw light across to the opposite walls. This ensures that the entire space is evenly lit, as vertical illumination would create shadows on the curved walls. The LED strip is warm white (2700k), chosen for its softness, to fit with Tremenheere's rural setting. Due to its remote position, the lighting of the Skyspace is powered by a solar panel, creating a cycle where the sun powers the light that follows it in the dusk.

The control system for the lighting scheme is based on an astronomical time clock; the onset of dusk triggers a forty minute dimming cycle, where the intensity of the light gradually dims to 50%, then slowly brightens again to 100%, creating an effect James Turrell calls 'chasing the twilight'. As the artificial light dims at a similar rate to the natural light, the edge of the aperture - where the sky meets the Skyspace - appears to vibrate slightly.

Unlike other Skyspaces, the lighting of Tewlwolow Kernow does not change colour; it is always warm white. However, the viewer’s perception of the light colour changes gradually during the dimming cycle. At sunset, the sky is a rich mid-blue and the walls take on a peach hue, but as the light slowly dims, the sky above darkens to midnight blue, and the walls appear cream. In the final stage, once the lights have returned to full brightness, the sky is a thick, opaque black, a stark contrast to the bright white of the curved walls.

The power of the Skyspace is in its simplicity; the interplay between the natural light and the artificial.

Photo Credits: Dr. Armstrong, Eleanor Bell & Ali Braybrooks