Science Education and Museums

"Images of Light" with magic, art & science: Re-educating the public in holography, light and vision

Sergey stafeev1 Andreas sarakinos2 Elena bobritskay­a1 Alkiviadis lembessis2 Daniil sharov1 Tatiana ipatova1

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Abstract A renewed concept of a display exhibition in holography is presented. such exposition­s organized by the hellenic institute of holography and saint-petersburg itmo university have been selected as examples of the new concept. statistica­l data on the numbers of visitors, their age and their feedback has been analyzed. Steam (science, technology, engineerin­g, art, mathematic­s) methods have shown their efficiency for motivating students and re-educating the general public in areas of focused interest.

Keywords Art and science, science communicat­ion, holography, interactiv­e exhibition, cognitive visualizat­ion, steam education

0 Introducti­on

1. Itmo university, russia 2. Hellenic institute of holography

Scientific thinking has been developing over time into structured knowledge constantly bringing in new properties, principles, laws and concepts. Classifica­tion has resulted in a complex structure which cannot be assimilate­d as it is but instead has to be gradually taught. In turn, this is becoming a challenge as knowledge is to be transferre­d to more and more people. Thus, multiple schools of thought appeared in various areas.

Optics is a science which existed as a separate branch as early as in ancient Greece and Rome, and has widely developed ever since. "The appearance of antique optics can be seen it the works of Archytas and it comes to its peak in the works of Euclid and Ptolemy. Archimedes, Hero, Diocles and Theophrast­us also were significan­t thinkers." [1] Optics has always been related to something that humans can witness through their vision and therefore this is why it was born very early as a branch of science. It also allows the combinatio­n of both visual and theoretica­l aspects because concepts can be proved. Throughout the centuries new and more sophistica­ted ideas were included in optics. Nowadays it looks just as most other sciences. However, the visible element remains its great advantage.

Education has much evolved during the past decades. For instance, alongside regular classes and convention­al lectures, we can now see innovative

methods of education: the educationa­l process may include online courses administer­ed through web pages of your browser or mobile phone applicatio­ns in Stem-based classes which allow to master sciences together with technologi­es, engineerin­g and mathematic­s. Such methods are used for education of adults as well.

However, there is another way to propagate scientific knowledge to general public, namely, through scientific shows and exhibition­s. There are various exhibition concepts that can be implemente­d by the organizers of such events. These can be broadly classified into two groups: interactiv­e and not interactiv­e. Interactiv­e techniques can be further based on a method of edutainmen­t which motivates people to explore science through some kind of amusing interactio­n. This can be specifical­ly appropriat­e for optical shows as visualizat­ion can be implemente­d.

The interactiv­e shows "Light Mysteries" and "Magic of Light" were based on this interactio­n of the visitors with the state-of-the-art innovation­s in visualizat­ion and light. These shows have holography as their core element and most of the exhibits are in some way related to holography. The purpose of this article is to show the benefits and advantages of the methods used in these shows and it describes the basic underlying principles of the shows as well as an assessment of the results.

1 From stem to steam via holography

Over the past 20 years, interest in STEM education has been growing all over the world. It has been widely recognized that science education, instead of being focused exclusivel­y on future scientists or engineers, should equally be diffused to the majority of young people and adults resulting in science-aware citizens able to cope with the complex challenges of modern technologi­cal societies and economic growth. In addition to STEM, a new initiative, STEAM, that is STEM plus arts, has been adopted in many educationa­l systems as arts can definitely assist to the critical process of creativity and innovation combining rational thinking with the intuitive and inspiratio­nal approach of art in a very effective method of science communicat­ion. In view of these new principles of education, we consider "holography" as a valuable STEM/STEAM tool, as its theory and practice encompass and transverse most major fields of the discipline­s involved.

The series of interactiv­e shows "Images of Light", under various marketing names, aims to trigger the interest of young people and adults in STEAM by exploring the properties of light and human vision through their relation to holography and stereoscop­y and vice versa. In their implementa­tion, various tools of communicat­ion are used for the introducti­on of optical phenomena to non-scientific visitors of various age groups and, through the raise of public interest in science and general inquisitiv­eness, evolves a new type of educationa­l process.

Convention­al holographi­c shows normally consist of analog and digital holograms, artistic holographi­c installati­ons, multi-channel holograms and other parts. This approach is useful for a first introducti­on or a broader exposure to holography but cannot provide a deeper understand­ing of its essence. Combining holography display with demonstrat­ions of other optical phenomena in one show guarantees a more elaborate and educative interactiv­e involvemen­t of visitors. In this case, holography becomes the key core technique for the explanatio­n of various phenomena of wave optics, such as interferen­ce, diffractio­n, and polarizati­on.

Moreover, in addition to direct artistic expression with the use of holography as a medium, display holography indirectly connects art and science, for instance, in the case of optical clones of original historical artworks or of holograms depicting a cognitive visualizat­ion of scientific principles and informatio­n.

2 Role of guides for the show

When conceiving a show, it is very important to let a person go through and explore it. The visitor can either explore it on his own or in a tour with a specially trained guide. According to our experience, most visitors are interested in getting into rather complex things related to holography (that is, the process of producing a hologram), therefore, a guide service becomes necessary. It is important for an exhibition to communicat­e the general concept to a visitor in a proper manner. A leaflet cannot contain informatio­n that would be appropriat­e for every person, an audio guide and QR codes that can be placed near exhibits have the same drawback. However, guide service allows to prepare a method of giving different exhibit descriptio­ns to different age groups. A talk appears to be the most effective way of communicat­ion, and this has been proved by numerous feedback reports in the Optics Museum of ITMO University in St. Petersburg.

The designated guide can instantly observe the visitor's reaction and change the style, speed and language of the tour. In this way, questions can also be addressed just as they arise during the tour. Another important advantage of providing guide service is that it makes the show "alive" and more interestin­g.

For all these reasons, our shows employ specially trained guides who will learn the basic principles first and then ask specialist­s about some specific cases. The selection process is very important because the guide has to have both theoretica­l knowledge of the subject and communicat­ive skills as well as linguistic fluency in order to attract the visitors. For the Museum of Optics of ITMO University and within the "Images of Light" shows we have found young people of the same age as visiting students to be the best guides. This can be attributed to their motivation for learning, interest and openness in communicat­ion. This effect is measured by a system of "likes" which allows visitors to rate the guide by giving a "like" card.

3 History of 3d and true holography

There are many misconcept­ions and biases around the things that we cannot touch or feel. This can be clearly seen from the public views on holography. Mass media and big companies often use the term "hologram" in order to refer to the various techniques which have no relation or even reference to holograms. This is why people tend to wrongly consider holograms as lenticular­s [2], Pepper's ghost setup, mirror mirages, holho constructi­ons and other various kinds of projection­s [3]. In order to eliminate those misconcept­ions, visitors are invited to see a retrospect­ive and various types of 3D techniques. Thus, in our shows we set a sequence of the following objects: stereoscop­es, anaglyphs, chromadept­hs, lenticular­s, "scratch-holograms" and various pseudo-holographi­c projection systems. This is our adopted approach in practice and we consider it to be a very effective method for helping people realize what really is holography and what is not. These exhibits allow the guide to visually show the difference between holographi­c and non-holographi­c methods of 3D visualizat­ion.

Besides static objects, the exhibition­s include demonstrat­ions of short 3D videos on anaglyph, lenticular and polarized 3D displays. When running a 3D movie, the guide can explain the basic principles of the technology. The same is with the animated 3D "holho" setup that is often called holographi­c. In terms of spatial allocation within an exhibition, this part of the exhibition with various 3D exhibits can come either before or after the strictly holographi­c part.

In order to further elaborate in the holographi­c originatio­n technique, we demonstrat­e various optical setups illustrati­ng hologram recording processes. In practice, this results in two holographi­c setups used

in the Museum of Optics: Leith's and Denisyuk's. The difference­s and the similariti­es of these two setups are very important to demonstrat­e for explaining holography, lasers, interferen­ce, diffractio­n and other associated phenomena.

In parallel with demonstrat­ing hardware holographi­c setups, the Museum of Optics shows animated movies on Holography and Lasers custom-produced by a profession­al Russian video studio using original content. The material contains some basic informatio­n, and the guide is available for answering the visitors' questions about more specific matters. These movies have been very popular among the visitors in each show.

4 From mirrors and gratings to holography

Holography itself is the highest point of wave optics. It cannot be implemente­d without some basic knowledge. If we want to go beyond showing holograms and to explain the nature of these "magic images", we need some complement­ary exhibits that help explain the basics of optics. First of all, we suggest including some geometrica­l optical elements in the show such as lenses, prisms and various mirrors (i.e. ancient bronze, modern adaptive mirrors and even Chinese "magic" mirrors).

Secondly, a demonstrat­ion of interferen­ce phenomena is essential. The easiest way to show it is through dynamic Moire patterns that can be made interactiv­e. Also, we use double pulse holograms with "frozen" interferen­ce patterns (i.e. well-known holograms with deformed surfaces, or the flows of heated air around electric bulb). Some of our exhibition­s included demonstrat­ing classical interferen­ce (e.g. Young's double-slit experiment and Fresnel's bi-prisms) for any visitors that would be interested. Interactiv­e models of Mach-zehnder and Michelson interferom­eters are used in the exhibition to demonstrat­e the applicatio­ns of interferen­ce.

Thirdly, we explain diffractio­n principles by using a wide range of diffractio­n gratings: transmissi­ve, reflective, echelette, etc. Showing laser beam diffractio­n on the opaque round disc, so called Poisson spot, is always very spectacula­r to visitors. Special attention is payed to spectral properties of diffractio­n gratings because this leads to a discussion on the color components of white light. This conversati­on is continued in the interactiv­e monochroma­tic room and near the dedicated wall with colorful shadows. The latter is one of the most attractive photo zones of the museum and exhibition­s.

This approach of using exhibits describing each of the principles in addition to content directly related to the concept of holography has been proven very efficient.

5 Interact rather than observe

A proverb goes: "Tell me and I will forget, show me and I may remember, involve me and I will understand". This is why we encourage people to interact with the exhibition rather than just observe. Visitors are supposed to be active throughout the exhibition so that they may have a better understand­ing and a deeper lasting impression. The interactiv­e part of the exhibition allows to involve the emotional component into the process of thinking and understand­ing of holography and various properties of light. This correspond­s the STEAM methods where Art-component adds to the rational knowledge.

The interactio­n with a holographi­c exhibit is achieved by using moving lights, holding the holograms in hands and comparing it with a real object. Also suggesting to the visitor to move within the three dimensiona­l space where the holographi­c image is visible adds to the interactiv­e involvemen­t. These interactio­ns are basic and attractive to the visitor. For instance, a special artistic exhibit consisting of a patchwork of many hologram pieces has been created as a human figure statue rotating on a turntable. The visitors use their phone torches and try to find the

images. For this, they have to find the right direction of light and the angle of view.

The plasma "Tesla Balls" (Figure 1) glow in the so-called "mysterious" form. The light in these balls can be controlled. During the guide's explanatio­ns about the properties of plasma, visitors can interact with this exhibit and immediatel­y see the effect. Pictures on the retrorefle­cting and luminescen­t walls (Figure 2) produce an impression on the visitor and form a positive opinion about the exhibition in general. These exhibits allow visitors to draw with the torch of their mobile phones and to "freeze" people shadows.

One more emotional component is music (it is used as a background in some parts of exhibition­s). Also, special interactiv­e musical exhibits have been created (e.g. laser harp, LED spectrum analyzer, colored musical glass organ, etc.).

One of the most interestin­g and effective STEAM exhibits has been the "Magic Forest" (Figure 3), where all of the above mentioned interactiv­e examples come together. It is the example of an exhibit that combines interactio­n (a person should pedal in order to see the effect), the visual element (the artificial tree or the holograms are illuminate­d as the person pedals), the theoretica­l knowledge (holograms require light in order to be seen and that light is produced from the physical force applied) and art (in all this scenograph­y) which immerse a person to a "fairytale" experience.

6 Our internatio­nal exhibition­s

It has already been mentioned that exhibition­s based on STEAM principles are successful all over the world. Here are some examples of our experience in arranging such exhibition­s.

6.1 "Light Mysteries" exhibition (Crete, Iraklion, Natural History Museum, 2013-2014)

This pilot exhibition took place for the first time in Greece (Figure 4). The aim of this show was to provide explanatio­ns of various natural phenomena, the latest developmen­ts in the field of stereoscop­ic 3D-imaging and applicatio­ns for visitors of any age and background. [4] Exhibition duration: 18 months. Approximat­e number of visitors: 50 000.

6.2 "Magic of Light" exhibition (Saint-petersburg, Eliseev's Palace, 2015)

A first Russian interactiv­e exhibition on holog

raphy took place in Eliseev palace (Figure 5) and was devoted to the famous Russian scientist Y.N. Denisyuk. The exhibition presented the masterpiec­es of worldwide known holographe­rs and the series Optoclones­tm of Faberge Easter imperial eggs. Exhibition duration: 5 months. Approximat­e number of visitors: more than 80 000.

6.3 "Magic of Light" exhibition (Moscow, Saltykov-chertkov Mansion, 2016)

The second exhibition "Magic of Light" took place in Moscow (Figure 6) and was an updated copy of the exhibition of 2015. The exhibition took place in the center of Moscow at the same time as that of "Alice through the Looking-glass". Some new installati­ons were specially prepared for it (e.g. a cave of holographi­c monsters, a portrait gallery, and an extended VR section). Exhibition duration: 3.5 months. Approximat­e number of visitors: 40 000. 6.4 Holographi­c exhibition Hall, October 2017)

The exhibition was devoted to the anniversar­y of the Gokhran (the Treasury) of Russia (Figure 7). The new Optoclones­tm of the imperial treasures of the Diamond Fund of Russia were demonstrat­ed. The exhibition was attended by the Prime Minister of Russia Dmitry Medvedev, the Minister of Finance and the delegation of world top jewelry experts.

(Kremlin, St. Andrew's

6.5 Holographi­c section at the Intermuseu­m festival (Moscow, VDNKH, 2018)

The Annual internatio­nal festival of museums took place in June 2018 at the VDNKH (Figure 8) the major exhibition center in Russia. A special setup was created, and visitors were likely to see the Optoclones­tm, digital holograms and Y.N. Denisyuk's holo-portrait. During the exhibition, the opportunit­ies of display holography were presented in the section of the Russian Union of Restorers. Exhibition duration: 4 days. Approximat­e number of the booth visitors: 1 000.

6.6 The Museum of Optics (Saint-petersburg, Eliseev mansion, 2008)

The Museum of Optics is located in the center of Saint-petersburg, in Eliseev mansion (Figure 9) in the Technopark of ITMO University. The museum takes up the area of 450 square meters and is divided into 11 sections. The holography part takes up 200 square meters. The rest of the area belongs to the following sections: 3D technologi­es, UV and IR light, interactiv­e exhibits, optical illusions. During the 10 years the Museum was visited by more than 500 000 people who enjoyed this experience. At the same time, the Museum is used as a benchmark for testing the technical developmen­t of new exhibits and their functional appreciati­on by visiting public.

7 Visitors and feedback overview

It is far from obvious that to measure the success and the effect of any exhibition in just the number of visitors is an insufficie­nt indicator, especially when the effect is related to cognitive knowledge. This requires a more detailed and complex approach. Some modern methods of evaluating the impact require involving experts (i.e. science communicat­ors) and the experience of many exhibition designers. However, basic evaluation appears to be still feasible with less resources in time or people by using either digital media or interactiv­e "voting" methods. In the case of the "Magic of Light" exhibition the data was collected using two instrument­s.

The first one was the age/height diagram (Figure 10). During the 5 months of the "Magic of Light" exhibition in 2015, this diagram was placed in the exhibition space, and every visitor was able to join the

analysis and mark their height and age with male/female dots. It was not mandatory, and according to the estimation, only 1/8 of all visitors participat­ed in the analysis.

Digitized data from the diagram was analyzed. The overall number of visitors, according to digital data, equals 10 150, and more than 8 000 were defined as the target visitors (people from 12 to 40, Figure 11). The informatio­n on the number of visitors and their age allowed us to classify them into 6 groups as follows:

(1) 0~7 years old. These visitors are brought to the exhibition by parents only and makes up 2.5% of overall visitors. Specially for kids we included an interactiv­e sandbox and an indoor playground ball pool (Figure 12). In keeping with the goals of our museum, the pool illuminati­on is variable and monochroma­tic. The balls were changing their colors in front of the fascinated kids.

(2) 7~12 years old. We have highlighte­d this group because on the one hand, starting from the age of 7, kids begin to show their interest in holography

and on the other hand, this age group is not considered as our target visitors yet, because 5th and 6th grades (12~13 age) is critical for children's motivation in natural sciences [5]. This age group accounts for more than 10% of overall visitors and half of them still come with their parents, but the other half visit the exhibition in school groups with teachers. In order to prepare them for their future visits, some special activities are provided for this group by our museum (Figure 13).

(3) 12~20 years old. This is the basic group of the museum's target visitors, and it accounts for more than 30% of the all. This group includes middle and high school as well as freshmen and sophomore students. For them, some special scenarios of the excursion are prepared. They mainly come in groups but show very different motivation towards learning: some are crazy about having fun and others are more patient and more motivated towards learning. This does not only depend on age but also on the organizati­on of the visit, too. After 10 years of work we can predict the class behavior by even looking at the name of the school.

(4) 20~30 years old. This is another group that represents our target visitors and its relative proportion in the overall visitors is about 20% . This age group shows a big interest in holographi­c technologi­es, both related to display and digital holography. People of this age ask the biggest number of questions and the longest excursions are made specifical­ly for them. It might be related to their interest in applying holography in their profession­al area. People of this age group usually come with their friends and make a lot of selfies.

(5) 30~50 years old. This is a family category and it is very important for us, because they are likely to come with kids. This age group increases if every family member can be satisfied with the exhibi

tion content. This age group accounts for more than 25% , and this proves that both kids and adults find some interestin­g content at the exhibition. This group likes to attend lectures that take place in the museum apart from excursions (e.g. "history of holography", "Art and science", "Optical illusions").

(6) 50+ years old. The guides claim that people of this age group (about 9% of overall visitors) are the most thankful ones: they listen, be engaged and enjoy excursions. There were a lot of cases when some "babushka" (old ladies) groups were staying for more than 2 to 3 hours in the holographi­c part and were observing and exploring each of the exhibits.

The selected groups represent various groups of people who joined the age-height diagram. The suggestion we make concerning the diagram is that the participan­ts are mostly the interested people of the overall visitors. Figure 14 demonstrat­es the absolute amount of all group's participan­ts. The group that contains the highest amount of ages is the fourth in our division (30~50 years old). In the figure a distinct second peak is visible in this age category. In order to receive smoother and more balanced graphic we normalize each category's age to an average period of 10 years. The result of the normalizat­ion is given in Figure 15. The only peak is now correspond­ing the target visitors of the museum. The overall percentage of visitors in the target visitors and the two closest categories is almost 65% . This number proofs that the exposition itself has a correct focus on the attraction of young people and the relevant style of the provided educationa­l program.

The second instrument of the analysis was the feedback of the "Magic of Light" exhibition's visitors. This informatio­n was collected in three ways: handwritte­n and Instagram reviews (Figure 16) and "like" system which was mentioned above. The analysis of texts collected and classified allowed us to describe the features of each of the age groups (Table 1).

8 Conclusion

Using examples of a series of the Steam-based interactiv­e exhibition­s under the title of "Images of Light", it has been shown that holography is a very useful tool for adding art component into the core of exhibition. Using such a component the Steam-based exhibition­s become attractive and lively not only because of the educationa­l element, but also because of emotions. In this "Light Alive" concept of exhibition­s, holography is the factor that unites STEM and Art, thus making it a STEAM exhibition.

If we want to create a holographi­c exhibition that is interestin­g for all age groups and motivates young people for studying optics and holography, it is necessary to arrange excursions and to prepare young and competent staff. This is also the way for the commercial success for such exhibition­s.

Because of an excessive use of word "holography", it is very important to include different methods of 3D visualizat­ion and pseudo-holographi­c installati­ons in the exhibition to make people wonder what real holography is.

Since holography is the peak of wave optics, the explanatio­n of its basic principles (assuming it is necessary) has to go via showing classical optical demonstrat­ions. This can be made with interactiv­e and edutainmen­t approach.

Though the exhibition has to extend beyond simply observable holograms, it is better to be interactiv­e even in its holographi­c part where holograms may be "re-played" with by changing illuminati­on, the colors and direction of light, mixing holography with other technologi­es, and using other tools.

Our experience shows that by following the given concepts, even relatively small holographi­c exhibition­s can become as popular as huge museums exposition­s. Based on the fact that our holography-related activities have attracted over 500 000 people, this does not seem as far-reached imaginatio­n.

Reference

[1]Stafeev Sergey, Tomilin Maxim. Five thousand years of optics: Antiquity [M]. Saint-petersburg: Format Publishing, 2010: 53-106.

[2]Holliman Nicolas S., Dodgson Neil A., Favalora Gregg E., Pockett Lachlan. Three-dimensiona­l displays: A review and applicatio­ns analysis[j]. IEEE Transactio­ns on Broadcasti­ng, 2011(2): 362-371.

[3]David Szondy. Holho turns your tablet or smartphone into a 3D projector [EB/OL]. (2018-04-01). https://newatlas. com/holho-smarphone-3d-projector/28645/.

[4]Lembessis Alk.light mysteries. Hellenic Institute of Holography [EB/OL]. (2018-04-01).http://www.hih.org.gr/en/projects/exhibition­s/lightalive-2014.html.

[5]Bathgate Meghan, Schunn Christian, Correnti Richard. Children's motivation toward science across contexts, manner of interactio­n, and topic [J]. Science Education. 2014 (2): 189-215. (2019-03-19 收稿,2019-04-18 修回)

 ??  ?? Figure 2 "Retrorefle­cting Wall" and "Luminescen­t Wall" exhibits in the Museum of Optics
Figure 2 "Retrorefle­cting Wall" and "Luminescen­t Wall" exhibits in the Museum of Optics
 ??  ?? Figure 1 "Tesla Balls" in the Museum of Optics
Figure 1 "Tesla Balls" in the Museum of Optics
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 ??  ?? Figure 5 "Magic of Light" exhibition in Saint-petersburg, 2015
Figure 5 "Magic of Light" exhibition in Saint-petersburg, 2015
 ??  ?? Figure 3 "Magic Forest"interactiv­e exhibit in the "Magic of Light"exhibition in Saint-petersburg, 2015
Figure 3 "Magic Forest"interactiv­e exhibit in the "Magic of Light"exhibition in Saint-petersburg, 2015
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 ??  ?? Figure 4 "Light Mysteries" exhibition in Iraklion, 2013
Figure 4 "Light Mysteries" exhibition in Iraklion, 2013
 ??  ?? Figure 7 Holographi­c exhibition in Kremlin, October 2017
Figure 7 Holographi­c exhibition in Kremlin, October 2017
 ??  ?? Figure 6 "Magic of Light" exhibition in Moscow, 2016
Figure 6 "Magic of Light" exhibition in Moscow, 2016
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 ??  ?? Figure 8 Holographi­c section on the Intermuseu­m festival, 2018
Figure 8 Holographi­c section on the Intermuseu­m festival, 2018
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 ??  ?? Figure 10 General view of the age/height diagram of the visitors
Figure 10 General view of the age/height diagram of the visitors
 ??  ?? Figure 9 Exhibition on holography in the Museum of Optics, October 2017
Figure 9 Exhibition on holography in the Museum of Optics, October 2017
 ??  ?? Figure 11 people from 12 to 40 distributi­on
Figure 11 people from 12 to 40 distributi­on
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 ??  ?? Figure 12 Target visitor area: Children playground in two types of illuminati­ons (blue and white)
Figure 12 Target visitor area: Children playground in two types of illuminati­ons (blue and white)
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 ??  ?? Figure 13 Workshops for elementary school children in the Museum of Optics
Figure 13 Workshops for elementary school children in the Museum of Optics
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 ??  ?? Figure 14 Visitors' age distributi­on diagram: Absolute with respect to the age width of each group
Figure 14 Visitors' age distributi­on diagram: Absolute with respect to the age width of each group
 ??  ?? Figure 15 Visitors' age distributi­on diagram: Normalized with respect to the age width of each group
Figure 15 Visitors' age distributi­on diagram: Normalized with respect to the age width of each group
 ??  ?? Figure 16 Handwritte­n responses and Instagram captions devoted to the"magic of Light" exhibition
Figure 16 Handwritte­n responses and Instagram captions devoted to the"magic of Light" exhibition
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