Feature, Hospitality/Leisure

How Da Vinci himself helped design the new lighting for The Last Supper

MILAN, ITALY–– Getting to see The Last Supper isn’t easy.

Visitors to Milan who want to lay their eyes on the iconic Leonardo da Vinci mural must buy tickets weeks in advance for a timed 15-minute slot. Only 25 people at a time are allowed into the convent refectory where the painting is displayed.

After passing through a series of sliding doors that keep out dust and moisture, they finally get a glimpse – and as of this month, they will see the 520-year-old painting like it’s never been seen before.

A brand new LED lighting scheme donated by iGuzzini has made The Last Supper’s colours and contrasts more vivid. At the same time, it has slashed energy use and excess heat in the building, opening up the possibility that more people might get to see it.


World famous

The world-famous painting – which shows Jesus revealing to his disciples that there’s a traitor in their midst – has lived through a lot. Commissioned by the Duke of Milan and painted between 1494 and 1497, The Last Supper was an experiment in painting on dry plaster – not a terribly successful experiment as it turned out, because even in Da Vinci’s lifetime the paint had begun to flake off.

“It was like painting with light”

Piergiovanni Ceregioli, iGuzzini

Since then it has been scratched, vandalised, and suffered restoration attempts that did more harm than good, including one occasion on which it was broken and glued back together. In the seventeenth century someone even knocked a door through Jesus’ feet. But this painting is a survivor: when British and American planes bombed the convent in 1943, the wall where it is displayed was one of the few left standing.

The Last Supper’s new lighting replaces a scheme installed in 2000 at the culmination of an epic 21-year restoration project. That scheme used fluorescent lamps to light it from below and halogen AR111 fittings for ambient lighting.

Not only did those fittings consume 3.5kW, they also brought huge amounts of heat into the room (the last thing delicate paintings need) and about a third of the light was spilled on to the adjacent walls and ceiling.

With the Expo coming to Milan this year, the city’s Architectural and Landscapes Heritage Office felt The Last Supper deserved better. So Italian manufacturer iGuzzini has ‘adopted’ the painting, designing a new lighting scheme and donating specially-made LED fittings.

The Last Supper follows other famous Renaissance artworks such as Michelangelo’s Sistine Chapel ceiling and Da Vinci’s Mona Lisa, in getting new LED lights (provided in those cases by Osram and Toshiba respectively).

With the help of art historians, architects and museum curators, the iGuzzini team developed the new lighting scheme last autumn, then visited the museum every Monday (when it’s closed to the public) from November to March to perfect the design and install it.

‘It was like painting with light,’ Piergiovanni Ceregioli, director of iGuzzini’s research centre, told Lux. ‘We were here with a computer, all the fittings were linked to the computer and we were saying, a little bit more of this, a little bit more of that… We would find a solution, stop, go outside, come back in, reflect, change it, stop, go outside again… it was ping pong.’


Mastery of light

Getting the lighting right is vital for any artwork, but particularly so for The Last Supper, because Da Vinci’s mastery of light is one of the things that makes the painting so special.

iGuzzini’s lighting design draws heavily on the lighting effects used by the Renaissance master in the painting.

The nine-metre-wide painting fills the wall at the north end of the room, and gives the illusion that the room continues into the picture, as if Jesus and his disciples are dining with us. Da Vinci’s tools for achieving this effect are perspective and light.

Just as the only daylight in the room comes from high windows to the left of the painting that cast light on to the opposite wall, so the right wall in the painting is shown brightly lit, while the left wall is in shadow.

Most of those windows are now shaded to protect artworks from sunlight. But the lighting design team preserved the effect by reducing light levels on the left side to 35 lx, compared with a peak of 50 lx in the centre of the artwork.

The design even takes into account the door that was knocked through the lower section of the mural in 1652, to ensure viewers don’t mistake it for an element of the painting. The lights were tuned to make the grey surface of the door easily distinguishable from the grey in the painting.

The new lighting consists of seven iGuzzini Palco spotlights, which have been specially modified for The Last Supper.

Barn doors on the luminaires direct the light on to the painting and keep it off the walls and ceiling, and Dali control gear dims the lights to exactly the levels needed.

“The Last Supper has always been marvellous in all seasons of its life. With this new lighting it will be even better”

Dario Franceschini, Italian minister of tourism and culture

The colour temperature has been warmed from 4200 to 3800K, and the colour rendering index is an impressive 95. The precise colour composition of the new scheme has been tuned to bring out the particular shades used in the painting, thanks to a custom-made chip-on-board LED light source. There was a particular focus on strong rendering of reds and skin tones, which have a habit of appearing washed out under poor quality LED lights.

Ceregioli says: ‘We have a colour temperature of 3800K, but it looks close to 3200K because you can see the warm colours are so deep, so powerful.’

He describes the results of the relighting project as ‘really fantastic’.

Ambient lighting in the room comes from freestanding fittings using iGuzzini’s Cestello LED product, replacing the old energy-guzzling halogens.


In a new light

Giuseppe Napoleone, director of The Last Supper Museum, said: ‘It’s a historic moment for me because I see The Last Supper with new eyes, with new light.’

From a conservation point of view, LED lights like these are perfect for delicate artworks because they’re pretty much UV-free. And the heat generated is over 30 times lower than the Italian and European standards for sensitive artworks, iGuzzini says.

The new lights reduce energy consumption by an enormous 83 per cent, cutting the lighting load in the refectory down to 570W.

So, as well as changing how the painting is seen, the lighting upgrade also opens up the possibility that more people might get to see it, because of the reduction in heat.

The room has space for dozens – maybe hundreds – more visitors than the 25 who are currently allowed in at a time, but first the museum’s conservators will need to be satisfied that it won’t harm the artworks.

Italy’s tourism and culture minister Dario Franceschini said at the unveiling of the new lighting: ‘Italy will have the chance to show the world its beauty, its culture and its heritage, and the work we’ve done over the centuries to preserve this heritage. The Last Supper has always been marvellous in all seasons of its life. With this new lighting it will be even better. It will be a good welcome to visitors who come to Milan.’