Son et Lumiere - St. Michael’s Cave Gibraltar

With nearly a million visitors a year, St. Michael’s Cave is one of the most popular attractions in Gibraltar, having fascinated guests since Roman times. Reputed to be bottomless, or linked to Africa, the cave has been the subject of myths and stories throughout the centuries.

With a lighting and sound system in need of updating, the Government of Gibraltar put out a very broad invitation to tender. As the Tourist Board of Gibraltar, who manages the caves and the project, wanted a single supplier and a ´turnkey´ solution, audio-visual company Electrosonic UK was called upon to put together a team of specialists.

Electrosonic UK
Nearly 40 years ago one of the first projects that the newly founded Electrosonic completed was a Son et Lumière show for the cave. Over the years, the system was upgraded piecemeal, but in 2002 the Government of Gibraltar decided on a complete refurbishment of the lighting and sound systems. The Electrosonic team included Paul Bason of Pure Media as the Show Creative Director, David Atkinson as lighting designer, Richard Northwood of Coms to work on the sound production and sound system, and Lauren Lloyd for all electrical and installation work.

The initial brief from the client called for a short day lighting show for visitors and an evening show for special occasions and visits. The real challenge was working to an open brief while being able to visualize the final result for Government approval. Using technology in a space with dampness, high humidity and salt corrosion was also something to take into consideration. The system also had to be easily maintained.

Lighting Designer David Atkinson
Lighting Designer David Atkinson of David Atkinson Lighting Design Ltd. commented, “The brief was to enhance the beauty of the space by subtle yet dramatic lighting, which should tie in with the script and specially composed orchestral score for this unique Son et Lumiere. It was certainly quite a challenge for the lighting design as there were no other elements apart from a very complex surround sound system. The lighting design was going to have to endure a twelve-minute period, creating drama and a sense of anticipation without appearing to be repetitive.”

The twelve minute Son et Lumière in the main auditorium, presented with all the general lighting off, plays a key role in helping tell a story of myth and legend. The fixtures David chose to use here consist of Martin intelligent MAC and Exterior units and generic lighting, as well as halogen floods fitted with toughened glass filters. Other special effects come courtesy of high-powered fans, haze machines and strobes. Lighting supplier for the project was UK-based AC Lighting Ltd.

Exterior and MAC projection
“Working in this magnificent space gave me lots of opportunity to utilize Exterior 600 (4) and Exterior 200 (5) sources positioned at strategic points around the cave, which produce deep dramatic hues of color such as ultraviolet to deep saturated reds. MAC 500E (2) and 250+ (4) fixtures are used to produce an array of beam effects such as projection, water ripples, fire effect dappled light, and simulated laser effects. High-powered Xenon flash tubes set below and inside crevasses simulate lightning and simulated gunfire while atomized water haze, used at set points to accentuate the shafts of light, simulate laser effects and allows a surface for projection.” Both the MAC 500E and MAC 250+ units are outfitted with custom gobos produced by Projected Image.

Challenges
The cave, although beautiful, did present quite a few problems, the main one coming from dripping stalactites. “During the summer months the humidity gets extremely high, which is probably worse than actual droplets of water as it can impregnate the equipment,” David states.  “Hence I chose to do trials at an early stage in the caves with various sources and came to a speedy conclusion that the Martin Exterior 600 and 200 was going to be the most suitable for strong controllable washes and reliability.”

Projection was also a concern, as the fixtures (MAC 500E and 250+) would need to pan & tilt. Therefore, they are fitted inside protective domes fitted with a fan and heater to keep a constant pre set temperature. All the incandescent lighting is based around the use of externally rated (IP65) architectural fixtures adapted to accept toughened colored glass.

Another challenge was the cave’s over two hundred concrete steps, which originally posed quite a hazard to the public. With health and safety in mind each step was fitted with an aluminum edging nose containing LED’s, which have proved to be extremely useful to all members of the public. 

“Hidden” scheme
On entering the cave the public are taken through an illuminated tunnel while a short narration repeats in Spanish and English. The tunnel is lit by a series of recessed, buried uplights, the effect creating bold shadows and adding to the sense of drama and anticipation. The splendor of the cave interior is accentuated through the use of 35-watt discharge fittings with spreader lenses and low voltage dichroic units. “The majority of the fixtures are positioned at a low level, hidden behind rocks and buried as the new lighting scheme had to be ´hidden´ in the caves, without the fittings being obvious to visitors. The color temperature of the lamps varies between cool and warm to add a sense of depth to the various cave chambers.”

Programming and control
All programming for the show had to be done overnight as the caves were open to the public during the day. Overall show control is provided by an integrated audio/video control system with remote show panels around the caves. Stewart Parker programmed the show with “in excess of” 100 lighting states to the compost soundtrack timecode on a lighting control desk and then downloaded the program onto a DMX replay unit. 

The installation took the electrical contractor three intensive months. The electrical works consisted of completely re-wiring and lighting the caves and installing the sound and lighting equipment.

In conclusion, David states, “The lighting design helps to portray a story and myths of the caves through various lighting effects and illusions, but more importantly the lighting is there to enhance the dramatic rock formations and splendor of St. Michael’s Caves.”

Team
Producer: Paul Bason
Lighting Design: David Atkinson
Lighting programmer: Stewart Parker
Sound design: Richard Northwood
Project manager: Ian Scott & Stuart Reid
Main contractor: Helvar Electrosonic
Electrical Contractor: Lauren Lloyd Electrical
Lighting Supplier: AC Lighting
Gobo production: Projected Image