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Smart LED Illumination in Vatican City

The OSRAM Podcast: Episode #1 with Martin Reuter


Hello and welcome to the Photonstudio, the OSRAM Podcast. My name is Dieter Schierer and I am an OSRAM employee in the digital communication department. I am very pleased to present the first episode of this new series. What can you expect here at Photonstudio? Exciting stories about light, or rather, about photonics. In lighting technology, there is already much more than just lighting. It's also about invisible light and sensor technology for transmitting information. All this is covered by the word ‘photonics’, and just as OSRAM is changing from a traditional manufacturer of incandescent lamps to a high-tech digital company, the meaning of light is also changing. In fact, visible and invisible light can be used to detect the environment. In traffic, for instance, it can communicate information to the environment at the unbeatable speed of light. In an increasingly networked world, light is thus becoming the technological backbone for new digital applications. I promise you, you will see light with different eyes. Who are our guests? OSRAM employees who work in a wide variety of areas and departments. From research and development to lighting designers and experts in sustainable business.

For our first episode, the upcoming Easter holidays have brought up a fitting theme - the new lighting in the Vatican. From the Sistine Chapel to St. Peter's Basilica, OSRAM has installed smart LED lighting for one of mankind's greatest art treasures. I have invited Martin Reuter to talk about this topic today. Among other things, he was jointly responsible for the installation in St. Peter's Basilica and I am very curious to hear from him how he has literally brought light to the 400-year-old works of art.

Dieter: Martin, welcome to the podcast. I am very glad that you took the time and that we can talk about OSRAM's Vatican projects today.

Martin: Hello Dieter, I'm also very pleased to be able to participate in this podcast and tell you a few things about the Vatican projects. I am curious to see what we will come up with today.

Dieter: Great, then thanks again Martin! Right at the beginning, can you tell us what your role is at OSRAM? What does a mechanical engineering graduate do now?

Maritn: Mechanical engineering studies have been over for quite a long time now. I've been at OSRAM since 1992, or rather I started at OSRAM Light Consulting in December 1992. There I was always involved in project-oriented customer business. I always like to tell people that my first project was the Riederstein Chapel at Tegernsee. After 25 years, the highlight of my professional development was to work in a team on the Sistine Chapel for the new lighting. And in between there were many customer-oriented projects, museums, factories, shops and also internet applications. To come back to the question, this has nothing to do with mechanical engineering anymore. It is now simply learning by doing.

Dieter: But you still need to have a technical understanding of the products you build or the sketches you make. Or how can you imagine that, when you think of this Riederstein Chapel at Tegernsee? What did you do there?

Martin: It was really about lighting design and for the first time it was about a custom luminaire of your own. Of course, as a mechanical engineer you have the advantage that you know a little bit about design. You know which materials have which properties and also how you can manufacture different things. That, of course, helps a lot. What you can't do as a mechanical engineer is, of course, the whole subject of lighting. You learn in physics that light is a wave or a particle. But you do not learn how to calculate light, what glare is, and what the criteria for good lighting are, you really learn that on the job and it's a lot of fun. It's also a new experience every day that you can make there.

Dieter: I believe you immediately, it sounds very exciting. Now let’s immediately go to the south, to our neighboring country of Italy. I mean, OSRAM has long history with Italy. If you think of Rome now, there's the famous Lampa da OSRAM in the forecourt of Termini station among other projects. The city and the country are also important for OSRAM. What projects has OSRAM ever done for the Vatican or Rome?

Martin: Well, I can't really speak much for Rome itself right now. Of course, everyone is talking about OSRAM there. As you say correctly, the Lampa da OSRAM was at the station forecourt, and unfortunately it no longer exists. We have also seen that some of our predecessors have already worked for the Sistine Chapel. Together with Siemens, the lighting solution was built in the late 80s. There is even a commemorative plaque when you leave the Sistine Chapel, where OSRAM is mentioned by name. So, we were already very well known in the Vatican at that time, how it started in 2013. OSRAM has a long history in Italy, and its headquarters are in Milan. But, of course, Rome, as the capital of Italy, is also equipped with many projects of OSRAM.

Dieter: Martin, you have now mentioned the Sistine Chapel as one of the projects in the Vatican. It is a world-famous sight, and it houses some of the most important paintings in history. Spiritually and culturally speaking it is also a very important place where popes have been elected for thousands of years, and where Michelangelo's frescoes captivate thousands of visitors every day. The project was completed in 2014 and has since been seen in a new light. But the question is, in what light? What was special about the project from a technical perspective and where was OSRAM significantly involved?

Martin: You have to look at the light from different angles. Firstly, with regard to color quality. Especially in art, it's important to combine the spectrum of light so that art is presented in the best possible way for the visitor. This means that you have to say goodbye to the obsession with saving money, which we often saw at the beginning of the LED era, when there was no importance given to quality but only to the quantity of light. In this context, this means that we did not only work with a white LED, but also added an extra LED to the spectrum at the edges, towards red and blue. And with the white converted LEDs there is also a so-called cyan gap, which we also filled in, so that we were able to create a spectrum that was as homogeneous as possible for the optimal color reproduction in the Sistine Chapel.

Dieter: I think color rendering is one thing, but from a purely technical point of view, when the frescoes are so old, and any external influence, be it light, moisture or even a draft, can damage everything, what needs to be done to ensure that the light does not damage the artworks?

Martin: The next aspect is of course that, in addition to optimal color rendering, the art is of course also optimally protected. This is where the LED is particularly suitable, because the light is completely UV-free. This means that UV radiation is a very short-wave radiation, and the shorter the radiation, the higher the potential for damage to materials, colors and actually all things of daily life. You can do this very well by yourself in an experiment. Let's put a newspaper on the windowsill and after the next sunlight you can see very well how the newspaper has faded. The same thing happens with the colors in the Sistine Chapel. There we made tests with the laboratories of the Vatican. We did stress tests with different pigments and mixtures. The colors used to be prepared with completely different materials, e.g. protein, glaze colors etc. The LED lighting bravely passed those tests, so that we can now be sure that the light will allow the art to survive and that the next generations will still enjoy it and see no changes.

Dieter: This means that based on these experimentally determined values, special LEDs were produced?

Martin: The LEDs themselves are standard LEDs that we have put together from the Opto Semiconductors range. Of course, we have especially selected the LEDs so that the color differences are minimal. But by mixing the individual colors, it was then possible to ensure the optimal color rendering and protection of the paintings.

Dieter: The Sistine Chapel project was completed in 2014, after which the Raphael Rooms were installed. These are also frescoes, were the same luminaires installed there or did you have again different requirements there? How did you proceed?

Martin: Maybe we'll go back to the Sistine Chapel to finish the topic there. Because there are two different lighting systems that were developed there. One is the normal visitor lighting, which we call Volta lighting. This is an invisible lighting for the visitor, meaning he only sees the light effect. There is a frame at a height of ten meters in the Sistine Chapel. This Volta lighting is installed there, which shines upwards and evenly, and homogeneously illuminates the vault with the world-famous paintings of Michelangelo and the wall paintings. Then there is a second lighting solution, a so-called Gala lighting, which is only switched on when official appointments take place in the Sistine Chapel. So, there are church masses, concerts and of course the conclave being held. The lights have not yet had to prove themselves, thank God they haven't yet been used in real life, because that is usually connected with the resignation or death of an active pope. This Gala lighting is also invisible to the observer, which has brought with it the difficulty that this lighting is extended by motor and then only protrudes over this cornice and can reveal its full lighting solution.

Dieter: If you put that down to the Raphael Rooms, what was done there?

Martin: We found completely different conditions there. There was already an information column in the middle of the room. This one already contained an uplight, but with a much worse color rendering and also with much worse energetic values. We used a converted Volta luminaire there, which illuminated the rooms harmoniously and evenly without dazzling visitors in any way. The visitor does not even see where the light comes from. That's what makes this lighting so attractive, because you enter a room where you experience the abundance of art, but under no circumstances are you dazzled in any way. Being able to achieve this makes us very proud.

Dieter: Yes, I was also inside during the St. Peter's Basilica project, it was fascinating. And then the St. Peter’s Square project, which was completed in 2016 and is also an important one. What role did OSRAM play there and what is new there? Are they just lights or was something added?

Martin: Well, in that case they are just luminaires. They were developed for the statues that stand at the top of the colonnades, or they were additionally equipped with a glare screen. Also, we worked with Siteco luminaires for cost reasons. The goal was simply to illuminate St. Peter's Square, which had previously only been illuminated via the four existing candelabras and was really dark at night, and so it aimed to offer people a friendly and open impression of the entire square. This will now be continued in the next project, where we are currently in the realization phase. This is the facade of St. Peter's Basilica. It will be incorporated into this concept so that visitors are welcomed with a brightly lit, friendly and open square, even at night and especially in winter.

Without OSRAM                With OSRAM

Sistine Chapel ©Copyright – Governatorato dello Stato della Città del Vaticano – Direzione dei Musei

Dieter: I can only confirm this. On St. Peter's Square, it is probably the case that if the lights are brought to full power, which is normally never the case, then one can sit down on the square and read a book and have the feeling as if it was daylight. So much light is there now on the forecourt.

Martin: Exactly, we reach illuminance levels there and the 50 lux, which is respectable for a square. For energy-saving reasons, of course, in normal situations the illumination is only set to about a third of the normal level. But this is still far enough to feel comfortable on this place and to do things that one absolutely has to do, for example adjust the settings of the camera.

Dieter: That’s wonderful Martin! Now we move in the direction of the St. Peter's Basilica, one of the most fascinating sacral buildings and destination of millions of people from all over the world. How does it feel to be part of such a project?

Martin: It's actually hard to describe, because you are working on a unique project in this world. It is the center of the Catholic faith and it is the main church of the Catholic world. It is decorated with works of art, like the St. Peter’s Baldachin and of course the big dome. This is unique! You enter this building and you are overwhelmed by all these circumstances and it fills you with great gratitude. But, of course, you also have the burden of responsibility on your shoulders, that it should be correspondingly good and that you deliver a result here that should satisfy even a head of state like the Pope. Of course, you have to see it that way, he is an authority.

Dieter: That is certainly true, and the benchmark has been set relatively high. I'll read out some of the figures I took from the press release: state-of-the-art LED technology of OSRAM, 20 km of cable, 780 LED special lamps at a height of up to 110 m, over 100,000 LEDs and almost 90 percent energy savings. These are very interesting figures, which have been generated by the project at St. Peter's Basilica. Can you say something about them?

Martin: I think the figures speak for themselves. It was a lot of work to distribute 100,000 LEDs in a room with 20,000 square meters, and then to achieve optimal lighting of the vaults, the domes, the baldachin and the visitor area is of course an enormous effort. And, of course, a great deal of constructive work was also necessary at this point to design the luminaires in this way. Most of the luminaires are either built into the vaults or they are installed at a gallery located at a height of 30 m. It is simply an enormous effort to do this and then to integrate it into an existing overall system in the Vatican, which can be controlled from a central control station. So that the complete church mass of the pope can be played through smoothly, just like in a normal theatre. There is a control desk and then the person responsible for the lighting on that day can preset the scenes and can then call up scenes at the right time, for example when the Pope about to hold a church mass at the main baldachin

Dieter: OSRAM has apparently succeeded in this; I was in St. Peter's several times for marketing activities during the project and I could see all this there. I could even enter the control room, and everything was redesigned there. What particularly fascinated me was the fact that the head of the technical service had an iPad in his hand and when I asked him, for certain photos and video sequences, to illuminate only a certain area or to change the intensity and angle, he then simply set it on the iPad with 2-3 clicks. There I was fascinated! That means that all the light that OSRAM installed in St. Peter's Basilica is now completely networked. Connection, one of our areas of expertise, plays a big role here, doesn't it?

Martin: A very important role! First and foremost, we always work on a DALI basis and then go into complete digitalization via a connect interface. And, as you say, the whole thing is then networked and digitized to such an extent that the head of the technical service here can also switch the lighting in St. Peter's Basilica from his office and adjust it accordingly. This is really a field of competence, and we are very proud that we were able to realize it with the means at our disposal.

Dieter: But that means that if we were to think ahead now, the system that OSRAM installed in St. Peter's Basilica at the end of the project could be expanded. Most museums and cultural institutions would be interested in managing visitors and seeing how many people there in real time are to determine when it is overcrowded. Would it be possible with this system to install more sensors to measure this?

Martin: Actually, it is of course possible that we could then influence this system via presence detectors and get valuable data from the system for the operators. There is a lot going on at the moment and the VISN topic is something where we already monitor rooms and entire office floors with appropriate sensors and detect the presence and number of people. In this way, we can influence the lighting and also other trades.

Dieter: Now you probably should explain what VISN is. For us it is definitely a term, but I think for the audience it probably isn't one yet. So, what is VISN?

Martin: VISN is a system based on thermal and infrared sensors. These sensors are not like the normal sensors you know from everyday life, like in outdoor spotlights, for example, which turn on as soon as they detect a heat source. The VISN sensors have a higher resolution, we work with 80 x 80 pixels, meaning I can detect the number of people in a room with this number of pixels, like with a kind of thermal camera, and then I can count and evaluate peaks over certain periods of time. Of course, I can also arrange for things to be done later, such as cleaning services or refilling of equipment of vending machines. Here the operators of the rooms have a lot of data at their disposal and from this the appropriate conclusions and measures can be derived.

Dieter: This means that in this project, and generally in projects where OSRAM installs systems that monitor rooms to save resources, we are on our way in the Connection competence field. So here you can't say that this is just a lamp replacement, i.e. exchanging old heating beam halogen lamps with LEDs. Listening to you now, it must have been a high-tech topic here. Martin, I have one more question: The Sistine Chapel and St. Peter's Basilica have both been converted to LED. Is the light in the Sistine Chapel now the same as in St. Peter's Basilica? As far as I know, in the Sistine Chapel there are only frescoes that are ancient and worth of protection, and in St. Peter's Basilica there are mosaics on the vaults and the side domes. Were there other requirements for the material and the light or how did you proceed here?And one more question: I was told that the whole project started with a complete 3D modelling in the initial phase, so as not to disturb the operation and processes. Therefore, a 3D model of St. Peter's Basilica was built to simulate the effect and distribution of light. How was that done?

Martin: So, to the first part of the question: the light has the same quality. As already mentioned, we work with luminaires at the special focal points with different LEDs and light colors, which allow us to respond to the art in question in the best possible way. To the second question with the 3D model: that is correct, and it was an enormous effort to build such a model. But we now do this for all projects in the Vatican, simply to be sure from the beginning that the lighting solutions we propose can be approved by the responsible persons with one or at most two test setups. One can, of course, imagine that the installation of a light at a height of 30 m on a gallery in St. Peter's Basilica also involves appropriate protective measures. I cannot simply go up there and screw around during operations, but whole areas are blocked off and that is of course an enormous effort. This can be minimized by such calculations and simulations. That is why we work with modelling in all projects.

Dieter: A final question from my side: you've explained the technical side of things quite well now, but what was your feeling when the lights were officially turned on for the audience and guests for the first time? What was going through your mind?

Martin: Just like with the Sistine Chapel, it's actually an indescribable moment, a highly emotional moment. The most beautiful thing is simply when you see that people like it. Especially with the choir and the music, how step by step the light was switched on and only then you can see the silence of the people and this aha-effect. Then this mumbling in the crowd starts, because for the first time people can see the art in a light never seen before... Highly emotional, goose bumps, simply a fantastic feeling!

Dieter: Then a final question: it is indeed the case that light was installed in the side domes for the first time ever. The mosaics in the side domes were visible in normal daylight, but as soon as the dusk started you hardly saw anything, because in the end there were only these side windows in the domes that let the light through and that was it. With the new light it is really incredible that you can see every detail and every corner completely, like in fantastic sunshine...

Martin: That's how it is, people no longer depend on being able to see everything in St. Peter's Basilica in midsummer when it's 40 degrees in the shade. They can now do that even on dull winter days. And that's actually the nice thing, that the quality of the light is the same for everyone now. This is a great advantage, not only the domes, but also the vaults of the side aisles and side altars. Now we have a few things that we are still improving, where the responsible people came up to us during the operation and asked if we could light up a little bit on the statues etc. Of course, the different wishes from the ecclesiastical and the museum area come together now. We are still making small improvements, but the overall reaction is very positive. This also shows that we can now realize more projects in the Vatican. Starting with the Pinacotheca, the Necropolis, the façade of St. Peter's Basilica, the Sala Clementina and a wide range of other projects where the Vatican is now relying on our expertise, specialist knowledge and also on products from OSRAM.

Dieter: This is the perfect ending; you beat me to it. I actually wanted to ask, without giving too much away, whether you can look forward to furthering OSRAM projects in the Vatican. You have just explained that we can be very pleased and very curious to see what else will be put in a great light. So we should all remain excited and I'm looking forward to the next projects and thank you very much for your time today. That was a great conversation, thank you very much again!

Martin: Thank you very much Dieter, I wish you a nice day.

In this episode we heard from Martin about the requirements for the new lighting in the Vatican and how the smart LED light now also works in the Sistine Chapel on St. Peter's Square and in St. Peter's Basilica. But so that you can experience it live, OSRAM has created a virtual 360-degree tour of the Sistine Chapel and St. Peter's Basilica, which is of particular importance in these times of corona pandemic. Visit our website www.osram.com/vatican for further inspiration on the projects St. Peter's Cathedral, St. Peter's Square and the Sistine Chapel. I wish you all a happy Easter! See you in the next episode of Photonstudio with a new guest!

Experience the new lighting in St. Peter's Cathedral in 3D

Experience the new lighting in Sistine Chapel in 3D