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Restoring Lumino-Kinetic art

Mobile Lumineux 130, 1966, et Mobile Lumineux 267B (Bleu), 1970, made by Nino CALOS (1926 - 1990)
Olivier Steib
Traduction(s) :
Restaurer l’art lumino-cinétique

Résumés

Cet article résume les principales étapes de la restauration des deux « Mobiles Lumineux » de Nino Calos (1926-1990), conservés au musée d'Art moderne de la Ville de Paris, ainsi que les processus décisionnels qui ont accompagné l’étude. L’article se centre essentiellement sur les problèmes du système lumineux et de son obsolescence.

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Texte intégral

I address my best regards and thanks to everyone who gave me this opportunity, and have contributed to this study, especially the Fondation des Monuments Historiques for awarding me the funds that allowed me to acquire all the necessary equipment which made this restoration a success.

Introduction

1These two « Mobiles Lumineux » made by Nino Calos are part of the lumino-kinetic movement, and are actually conserved at the museum of Modern Art of Paris (MAMPV). Their purpose is to produce a picture, which combine light and movement. Most of the Lumino-kinetic artists, including Nino Calos, used the « moiré » pattern, which is an interference of light produced when you overlay two identical patterns and move them (in rotation or displacement). Those mobiles have been made in order to be hung on the wall, just as a classical painting, and thus invite the visitors to contemplate them.

Fig. 1 Mobile Lumineux 130, 1966, and Mobile Lumineux 267B (Bleu), 1970

Fig. 1 Mobile Lumineux 130, 1966, and Mobile Lumineux 267B (Bleu), 1970

The artworks before the intervention.

Credit © Steib O. 2013.

2Mobile Lumineux 130 is a smaller, early work, made in 1966. It’s producing a light effect consisting of moving dots of light, appearing and disappearing in haziness. It was acquired in 1970 by the MAMPV. It was seen in 1967, during the exhibition Lumière et mouvement1. Mobile Lumineux 267B is slightly bigger (90 cm against 60 cm), and was made 1970, and it represent a blue sphere moving into the space. This mobile joined the MAMPV collections in 1988. It was shown in 1983, during Electra2 exhibition at the museum.

3The two mobiles were first conserved in a reserve located under a basin, with high level of humidity, which certainly caused the main alterations we observed. Then, they were moved to the new reserves in Saint-Denis, which meet the requirements in terms of conservation.

Artist's biography

4Antonio Calogero (1926-1990), alias « Nino Calos » was an italian artist, self-educated, he studied philosopher and was quite fond of poetry, which fueled his practice. His first experiences with the light medium consisted in paintings, made using flakes, in front of which he placed flashing spotlights. This allowed him to produce a sensation of movement inside the painting. He encountered similar artworks during his travels to Paris, and especially the work of Frank Josef Malina, who quickly became a friend. Frank J. Malina was quite a peculiar artist, since he started his career as an aeronautical engineer, and especially building rockets during the conquest of space in America during the 40’s. This particularity can be seen through his artworks, since he made “electropaintings” suggesting the movement of stars. Nino Calos joined him in 1957. At the start, his works were similar in construction as the one made by Malina, using the Lumidyne system. Then, he started his own experimentations, using different compositions, colors, and shapes. He didn’t try to change the system though, as he wasn’t much confident to manipulate electrical devices. Nino Calos also made architectural integrations of his mobiles, such as mural panels, or kinetic environments. In the late 70’s, he went back to Italy, and attempt kinetic paintings on paper. Even then, we know that he was still making mobiles, until his disappearance in 1990.

Fig. 2 Nino Calos in front of his Mobiles Lumineux

Fig. 2 Nino Calos in front of his Mobiles Lumineux

Front cover of the book Nino Calos : Itinéraire lumino-cinétique, 1977.

Credit: © Jean-M. Bertholle, 1977.

History of  lumino kinetic art

5The lumino kinetic is an artistic movement from the 1950’s, which pursued the research started by the kinetic art, concerning the « virtual movement » and the « actual movement ». The first one is an apparent motion, an illusion, such as you can feel in front of a painting made by Vasarely, which seems to be moving, or an artwork made by Yaakov Agam which evolve as the viewer walk in front of it. The actual movement is a motion  created by a motor, as Jean Tinguely’s work, by the wind, as for Alexandre Calder, by the viewer’s hand, such as Yaakov Agam, or whatever source of kinetic energy which animates the artwork.

6Kinetic art is an art of experimentation, often using poor materials, and which shapes and styles greatly differs. Thus, we can find paintings, mobiles, machines, or installations asking for the active participation of the viewers, such as mazes. The Lumino-kinetic art was truly successful in the 1960’s, and could be seen through major international exhibitions, gathering an astonishing number of young artists, especially The responsive Eye presented at the Museum of Modern Art of New York in 1965, or Lumière et Mouvement in the museum of Modern Art of Paris, in 1967. This success was quickly followed by its decline during the 70’s. This may be explained by an overabundance of objects, which, by redundancy, lost their novelty and thus the public interest at the end of the decade.

Observations

Construction

  • 3  The reducer allows us to lower the output rotational speed, here at 1 RPM only.

7The mobiles lumineux made by Nino Calos were built following the « lumidyne system » made by Malina. They are made using a plywood box, at the bottom of which he placed a lighting system, using either fluorescent bulbs or incandescent lamps, and a kinetic system (a motor and a reducer3). A first geometric pattern (lines, dots) is then painted on a transparent plastic disk, which is placed on the axis of the motor, and called rotor. A second plastic screen, the stator, is placed above it, fixed, with another pattern. Finally, a third screen, the diffusor, is used to combine the two moving patterns, and produce a blurry image of light and motion merged together.

Fig. 3 Mobile Lumineux 130

Fig. 3 Mobile Lumineux 130

Building schematics of Mobile Lumineux 130

Credit: © Steib O. 2013.

8Concerning Mobile Lumineux 267B, Nino Calos replaced the second screen (the stator) by a grid made with sticks on which he draw a black circle cut regularly, in order to obtain more contrast and different kind of effects. Another work, Mobile Lumineux 231, also preserved in the MAMPV, was made using a curved diffusor, which produce a wave.

9However, most of the mobiles were built using the lumidyne system made by Malina, using the same materials, and also signed inside and at the back by the artist.

Alterations

10The two mobiles show the same alterations, probably caused by the condition of their conservation, especially some high levels of humidity.

Fig. 4 Details of the main alterations

Fig. 4 Details of the main alterations

Details of the main alterations found on the two mobiles.

Credit: © Steib O. 2013.

11A homogenous layer of dust is found on both mobiles, with a layer of dirt blocking the light and fading the colors.The paint was also affected, mostly on the side of the mobiles, with the development of moss, stains of metallic oxides, and a general weakening of the paint binder. A piece of brown adhesive tape was applied on Mobile Lumineux 130, and its glue entered the layer of black paint, which is bothersome. Microorganisms also made their way inside the mobiles, and developed themselves on the layers of dirt. The different screens inside are in good shape, but the diffusor present scratches and cracks, especially Mobile Lumineux 267B, heavily damaged. We noticed an advanced metal corrosion, both inside and outside the mobiles. The aluminum corners were deeply corroded, and a round shaped pattern was left by a wrapping paper, which retained water and caused the alteration.

12The general support of both the mobile is in pretty good condition, considering the fact that they are made in plywood which was exposed to water, which only caused a slight deformation. The corners were a bit worn due to shocks, and the screws were used several times already, causing their path to be slightly worn off as well.

Treatment proposal

13Beyond the usual alterations, frequently encountered in the field of conservation and restoration, we also found specific alteration concerning only mobiles and artworks using lights. These problematic encouraged the study and the restoration of these two artworks.

14The case of Mobile Lumineux 130 concerned the lighting system, which stopped working. The original fluorescent bulbs reached the end of their life, and the artwork “died”. These fluorescent bulbs, measuring 36 cm long for a diameter of 37 mm, aren’t available anymore, since a couple of years now, and we can only imagine finding some rare copies of those in collections. Moreover, this artwork was used to be plugged to a 127 V tension, which means that the motor, still original, must stay on this tension to work. The case of Mobile Lumineux 267B concerned the diffusing screen, which is cracked, which let the light go through, when it’s supposed to be diffused.

15These two problematic don’t have an obvious solution. There are no fluorescent bulbs left, of diffusing screens from the 1970’s. Still, the renewal of the lighting system is essential for the mobile to exist, and the diffusor no longer fulfill its role. In both cases, the picture is affected, when the light effect is truly fundamental to recognize the artwork.

16So, we considered several solutions, we had to validate before the treatment. In the case of Mobile Lumineux 130, we thought about substituting the old light system with a modern device, which can either use a similar technology or a more advanced one. Concerning the screen of Mobile Lumineux 267B, we found that there was no more 2mm thick PMMA screens produced nowadays. We therefore chose to attempt to restore the original, accepting that, if this attempt proved unsuccessful, we may be forced to replace the screen.

Treatment

Common treatments

  • 4  Triton X-100, 1% in demineralized water.
  • 5  Active substance : benzalkonium chloride.

17The first step of the treatment was removing the dust, using a vacuum cleaner. The second step was cleaning the mobiles using cotton and an aqueous solution4, since Nino Calos used vinyl paint for the black and white parts of the box, and a glycerophtalic paint for Mobile Lumineux 267B blue and Mobile Lumineux 130 white. Areas that showed moss and mold residues were treated using a biocide cleaning solution5. The brown adhesive residues left on the side of Mobile Lumineux 130 were problematic, because they were deeply embedded in the paint. We first gently removed the rest of the tape, making sure that the remains of glue stay on it. We then removed most of the dry adhesive residue with a scalpel, and the rest with a solution of white spirit and a surfactant, which helped remove the glue without it migrating into the support. We then treated the screens, made in PMMA, using a microfiber cloth and a demineralized water solution added with a surfactant. Oily residue and glue were then removed with the same White Spirit solution used before.

18Next step was the treatment of the metal corrosion. We used an ultrasonic cleaner to treat the small parts that we could remove easily, such as screws and bolts. The advantage of the ultrasonic cleaner is that the ultrasound will clean the oxides deposits into the narrow corners, which would be much more difficult to access, and less accurate with a manual abrasion. Once out of the bath, these elements were deposited in a passivating solution of potassium phosphate (or a tannic acid solution for outside screws, already colored in black). Every component we could not remove were cleaned and treated on site, using the same solution.

19The aluminum corners were more problematic. Aluminum is a highly reactive element, which has the useful property of being self-passivating : a whitish oxide layer instantly covers the metal exposed to oxygen, and protects it. However, this layer will continue to thicken, if the environment is conducive to oxidation. Then, once you get to a certain thickness, this oxide layer will form a flake and separate itself from the raw aluminum, and thus create holes. Moreover, following this oxidation, the four corners were also displaying a heterogeneous aspect. Since it was imperative to restore a harmony between them, we decided to polish their surface with a very fine abrasive. This allowed us to reduce the scratches and to improve the long-term lifetime in storage.

  • 6  Phenolic micro balloons and Paraloïd® B67 in WS, used in order to respect the solubility of the re (...)

20The support was treated, and the plywood delaminations were fixed using polyvinyl glue. The smalls holes located around the worn off corners were filled6, then retouched using gouache, which the duskiness suited our needs in this case.

Fig. 5 Details of the different treatment operations made on the box

Fig. 5 Details of the different treatment operations made on the box

 Before the cleaning, during the filling, and then retouching.

Credit © Steib O. 2014.

Treatment of Mobile Lumineux 267B

21After the common treatments, we then started to work on the consolidation of the PMMA diffusing screen of Mobile Lumineux 267B. As we stated, it was 2 mm thick, which cannot be found today, not with the same haziness anyway. We had to try and save it, and so we started looking for different technics to fill the cracks. Since the screen was really thin, and the crack was over 50 cm long, only a few adhesives were usable.

Fig. 6 Cracks and scratches analysis of the PMMA screen

Fig. 6 Cracks and scratches analysis of the PMMA screen

This step was made in order to estimate the chances of success and the feasibility of the restoration attempt.

Credit © Steib O. 2013.

22In terms of pure resistance, only the epoxy resins really stand a chance to support the significant weight of the screen that performs a constant pull on the sealing surface. The screen still weights 1 kg (2 lbs.), and is only resting on 1 cm on each side. We also had to consider that the temperature rises during the animation of the mobile. In terms of optical quality and aging stability, very few resins were available. In fact, there isn’t really an epoxy resin whose stability is truly recognized, that also had a sufficient viscosity for infiltration, and a refractive index exactly similar to PMMA (which is indispensable in order to obtain a perfectly invisible joint). The only resin that came closest to these criteria, and which has been repeatedly tested in the conservation field, was the HXTAL NYL-1. We ordered it for testing on small PMMA plates we prepared, to perform consolidation using three different methods. The first test was depositing the resin drop by drop along the crack. The problem we encountered was an irregular infiltration, and the fact that the drop deposits were hard to remove from the plastic surface without damaging it. So we tried to apply a temporary repositionable film to protect it, and reiterated the test. Then again, the infiltration was not good enough, since the adhesive was probably too viscous and wouldn’t penetrate properly (but the drip problem was avoided). We therefore tried one last method, using a sealed bag and a vacuum pump, which would -in theory- allow the adhesive to penetrate where the air is removed, that is to say, the crack.

23Sadly, despite several attempts, with several techniques of infiltration, we did not managed to get a perfect result, or a method which did not posed high risks in order to consolidate this type of crack. After these attempts, knowing that we were only working on small test plates, and that the consolidation of the screen would be much more of a challenge, we chose to act in caution.

24We then proceeded with the substitution of the original screen with an equivalent. We ordered a series of samples of all currently PMMA diffusing products available. We chose Plexiglas®, since it was the supplier that offered us the widest range for this type of product.

25By virtual and visual comparison, we then opted for two samples. We settled for the most faithful sample by consulting with the curator, Ms. Dominique Gagneux, and the teachers.

Fig. 7 Virtual and visual comparison

Fig. 7 Virtual and visual comparison

Virtual and visual comparison of the sample against the original, in order to settle our choice for a replacement.

Credit © Steib O. 2014.

26Since the minimum thickness of these plates was 3 mm, we had to remove 1 mm from the edges of the ordered screen using a milling machine, in order to insert it into the mobile.

  • 7  Microgloss®

27We also decided to polish the screen of Mobile Lumineux 130 to reduce the scratches on its surface, thus improving the visibility and the quality of the light effect. This slight polishing was performed with an abrasive fluid (solvent free7) designed and recommended for delicate plastic polishing. This really helped to recover a clean surface, and to alleviate the significant, deep scratches.

Fig. 8 Detail of the surface of Mobile Lumineux 130

Fig. 8 Detail of the surface of Mobile Lumineux 130

Before and after polishing.

Credit © Steib O. 2014.

Treatment of Mobile Lumineux 130

28Finally came the time of the substitution of the light system of Mobile Lumineux 130. This was truly essential for the recognition of the work, which is only a mysterious inanimate box without its lights.

29We first had to clearly understand the current system, how it was working, and especially its light properties. This was the first difficulty : while current standards allow a quick and easy identification of a fluorescent bulb, the original lamps were only labeled with a manufacturing brand. So we searched through the archives for information, in order to find the colorimetry and the light output of these tubes. We did find those in an old MAZDA catalog, which indicated that these tubes had a luminous efficiency of 700 Lm, and a color rendering index quite low. By correlating these data, we could identify that they were halophosphates fluorescent bulbs. In order to find the color temperature, which was not specified, we made a comparison using a spectral curve found in the catalog with another spectral curve referenced by the International Commission on Illumination (CIE). This allowed us to find out that the tubes had a color temperature around 4150 K, which correspond to a neutral white.

Fig. 9 Comparison of the spectral repartition

Fig. 9 Comparison of the spectral repartition

Comparison of the spectral repartition of the original fluorescent bulbs, found in a Mazda catalog, and the standard illuminant made available by the CIE..

Credit © Steib O. 2013.

30Since we had every pieces of the puzzle in our hands, we went looking for the proper equivalent light source. The first observation was that there weren’t any 36 cm long fluorescent bulbs left nowadays, and a 37 mm diameter was even less possible to be found. Second observation, the old ballasts were filled with a resin, and therefore it wasn’t conceivable to repair them, so they would have to be replaced. It was therefore impossible to consider a fluorescent source, not without having to heavily modify the entire light system.

31We then went to look at another technology, the light emitting diodes, commonly called LEDs (Light Emitting Diode). This technology is in constant development, and will eventually replace all existing energy-intensive and polluting sources, therefore fluorescent tubes which still contain mercury. LEDs does have many advantages in our case, since they are available in a wide range of colors, and are very small sized, which makes them ideal for adaptive systems. They are also interesting from the point of view of conservation requirements, since they don’t produce UVs, and a really low heat compared to the amount of light they emit. Their main attribute is an exceptional lifetime of about 50 000 hours. However, they also have disadvantages, the main one being the directional nature of the light source, as they act as spotlights and not diffusing lights, also the fact that they produce bright dots. Their light output was also insufficient, until very recently and the latest technology.

32We looked for light scattering solutions to compensate these defects, and thus we found out two possibilities: either by using a transparent PMMA tube, covered with a diffusing filter, such as the new generation which is currently developed by 3M®, or using a diffusing PMMA tube. By chance, we found an existing diffusing product with a 38 mm diameter, used for retrofit light system. This tube is made to hold a LED stripe, which is placed on an aluminum plate used for heat dissipation. Since we found all the elements, we decided to make our own custom replacement tube.

Fig. 10 Substitution tubes

Fig. 10 Substitution tubes

The different steps to make a substitution tube.

Credit © Steib O. 2014.

33We ordered the diffusing tube that measured 2 meters, and cut it to the desired dimensions, 36 cm. We also ordered a LED stripe with similar properties to those found on the original tubes, with a correction made to compensate the loss caused by the diffusing tube, which reduces by 30% the brightness of the light source behind it. We used aluminum bases we recovered on old fluorescent tubes from the 60’s we had in our hands. We thus had the opportunity to pay a small tribute to the original tubes. Those bases allowed us to insert the replacement tube just like the original ones into the sockets, inside the mobiles.

34Once the tubes were mounted, we adapted the wiring by making simple changes of connections, without affecting the original. The power supply that we had chosen was suitable to power the two substitution tubes (which consume only 10 W, against 32 W for the original tubes), and it was really small sized to be as discreet as possible. We placed it near the ballasts, reusing its screws. The intervention thus remained minimal and fully reversible, since no adhesive were used, and no changes had occurred on the original elements.

Fig. 11 Comparison

Fig. 11 Comparison

Before and after the mounting of the power supply and the substitutes.

Credit © Steib O. 2014.

35After tryouts, the result was successful, and for the first time we were able to observe the luminous effect produced by the mobile. We finally took some preventive measures. First, a label was applied on the power cable to recall the operating voltage, 127 V, in order to avoid an overvoltage and the destruction of the small motor inside the mobile. We also made a standard identification sheet to follow and identify the changes made on the mobile during its restoration, in order to facilitate the renewal of the light system if it was to break in the future. We also replaced the old electrical dominos by compact splicing connectors, which are much more secure.

Fig. 12 Mobile Lumineux 130 and Mobile Lumineux 267B (Bleu)

Fig. 12 Mobile Lumineux 130 and Mobile Lumineux 267B (Bleu)

Photography of Mobile Lumineux 130 and Mobile Lumineux 267B (Bleu) after treatment.

Credit © Steib O. 2014.

Conclusion :

36The former screen of Mobile Lumineux 267B will be stored along with the mobile, for a time when an adhesive and a truly efficient and respectful method of consolidation of the PMMA are developed. The fluorescent bulbs of Mobile Lumineux 130 will also accompany the artwork, for future references or analysis, if necessary.

37The study and restoration of such peculiar artworks were truly an opportunity, to deal with usual alterations on a wide variety of materials, while having to think of new, innovative solutions to an unusual problem which is not often faced during our formation.

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Notes

1 Lumière et Mouvement, museum of Modern Art of Paris, 18 May - 28 August 1967.

2 Electra, museum of Modern Art of Paris, 10 December 1983 - 5 February 1984.

3  The reducer allows us to lower the output rotational speed, here at 1 RPM only.

4  Triton X-100, 1% in demineralized water.

5  Active substance : benzalkonium chloride.

6  Phenolic micro balloons and Paraloïd® B67 in WS, used in order to respect the solubility of the retouched support.

7  Microgloss®

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Table des illustrations

Titre Fig. 1 Mobile Lumineux 130, 1966, and Mobile Lumineux 267B (Bleu), 1970
Légende The artworks before the intervention.
Crédits Credit © Steib O. 2013.
URL http://ceroart.revues.org/docannexe/image/4960/img-1.jpg
Fichier image/jpeg, 912k
Titre Fig. 2 Nino Calos in front of his Mobiles Lumineux
Légende Front cover of the book Nino Calos : Itinéraire lumino-cinétique, 1977.
Crédits Credit: © Jean-M. Bertholle, 1977.
URL http://ceroart.revues.org/docannexe/image/4960/img-2.jpg
Fichier image/jpeg, 860k
Titre Fig. 3 Mobile Lumineux 130
Légende Building schematics of Mobile Lumineux 130
Crédits Credit: © Steib O. 2013.
URL http://ceroart.revues.org/docannexe/image/4960/img-3.jpg
Fichier image/jpeg, 848k
Titre Fig. 4 Details of the main alterations
Légende Details of the main alterations found on the two mobiles.
Crédits Credit: © Steib O. 2013.
URL http://ceroart.revues.org/docannexe/image/4960/img-4.jpg
Fichier image/jpeg, 732k
Titre Fig. 5 Details of the different treatment operations made on the box
Légende  Before the cleaning, during the filling, and then retouching.
Crédits Credit © Steib O. 2014.
URL http://ceroart.revues.org/docannexe/image/4960/img-5.jpg
Fichier image/jpeg, 840k
Titre Fig. 6 Cracks and scratches analysis of the PMMA screen
Légende This step was made in order to estimate the chances of success and the feasibility of the restoration attempt.
Crédits Credit © Steib O. 2013.
URL http://ceroart.revues.org/docannexe/image/4960/img-6.jpg
Fichier image/jpeg, 864k
Titre Fig. 7 Virtual and visual comparison
Légende Virtual and visual comparison of the sample against the original, in order to settle our choice for a replacement.
Crédits Credit © Steib O. 2014.
URL http://ceroart.revues.org/docannexe/image/4960/img-7.jpg
Fichier image/jpeg, 836k
Titre Fig. 8 Detail of the surface of Mobile Lumineux 130
Légende Before and after polishing.
Crédits Credit © Steib O. 2014.
URL http://ceroart.revues.org/docannexe/image/4960/img-8.jpg
Fichier image/jpeg, 2,7M
Titre Fig. 9 Comparison of the spectral repartition
Légende Comparison of the spectral repartition of the original fluorescent bulbs, found in a Mazda catalog, and the standard illuminant made available by the CIE..
Crédits Credit © Steib O. 2013.
URL http://ceroart.revues.org/docannexe/image/4960/img-9.jpg
Fichier image/jpeg, 572k
Titre Fig. 10 Substitution tubes
Légende The different steps to make a substitution tube.
Crédits Credit © Steib O. 2014.
URL http://ceroart.revues.org/docannexe/image/4960/img-10.jpg
Fichier image/jpeg, 412k
Titre Fig. 11 Comparison
Légende Before and after the mounting of the power supply and the substitutes.
Crédits Credit © Steib O. 2014.
URL http://ceroart.revues.org/docannexe/image/4960/img-11.jpg
Fichier image/jpeg, 880k
Titre Fig. 12 Mobile Lumineux 130 and Mobile Lumineux 267B (Bleu)
Légende Photography of Mobile Lumineux 130 and Mobile Lumineux 267B (Bleu) after treatment.
Crédits Credit © Steib O. 2014.
URL http://ceroart.revues.org/docannexe/image/4960/img-12.jpg
Fichier image/jpeg, 915k
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Référence électronique

Olivier Steib, « Restoring Lumino-Kinetic art  », CeROArt [En ligne], 5 | 2016, mis en ligne le 26 février 2016, consulté le 24 février 2017. URL : http://ceroart.revues.org/4960

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Auteur

Olivier Steib

Olivier Steib studied the conservation and restoration of sculptures at the Art School of Tours, in which he worked in 2013-2014 on the restoration of two Mobiles Lumineux made by Nino Calos, a Lumino-kinetic artist. Before that, he studied conservation and restoration in several fields at La Cambre, in Brussels, till 2011. He also achieved a License in Art at the University of Metz in 2008.

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Licence Creative Commons
CeROArt – Conservation, exposition, restauration d'objets d'arts est mis à disposition selon les termes de la licence Creative Commons Attribution - Pas d'Utilisation Commerciale - Pas de Modification 4.0 International.

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