A pragmatic approach to preventive conservation Lighting design

A pragmatic approach to preventive conservation Lighting design support for Madeleine Vionnet, puriste de la mode Exhibition at musée des arts décoratifs in Paris from August 2009 to February 2010. ICOM-CC Triennial 16 th Conference – 19/23 september 2011, Lisbon

Specificity of exhibition lighting The art of lighting is an integral part of an exhibition. Exhibition lighting contains two objective aspects: - impact of lighting on object conservation : three factors cause damage on objects, spectral sensitivity of the object, spectral composition of the light source and the total luminous exposure. - impact of lighting on visitor’s vision : lighting must give visitors a good view of presented objects, without glare, unwanted reflects or sufficient illumination. and one subjective aspect: - lighting for display is not only a challenge for visibility and conservation. As part of the spatial design, it must participate with the interpretation and be meaningful. In fact, exhibition lighting is a visual semiotic system. 2

Madeleine Vionnet Exhibition • Seven months exposure instead of the usual three months for a temporary exhibition. • The objects presented in highly sensitive materials (textiles) • A famous design firm to set the exhibition (Andrée Putman) • A large budget (patronage) • A place very structured (showcases) 3

The scenography • walls or ceilings, bright white • Walls or ceilings, matt black • Walls, ceilings or floors, glossy black 4

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The action of preventive conservation in lighting 1. To assist for the selection of light sources, 2. To decide of the total luminous exposure, 3. To propose different ways to achieve the goals of limiting the illumination 4. To be able to measure the light exposure 5. To measure of fading, 6. To review the actions 7. To make new proposals for future exhibitions 6

1. To provide assistance for selection of light sources Imposed by the lighting design project: - Fluorescent tubes T 5 28 W 830 Imposed by the existing installation: - Halogen MR 16 50 W 7

2. To decide of the maximum of total luminous exposure accepted Sensitivity and classification for cultural property The table below lists materials in four categories according to their sensitivity to light Category Description 1. No sensitivity The object is entirely composed of materials that are insensitive to light. Examples; most metals, stone, most glass, genuine ceramic, enamel, most minerals. 2. Low sensitivity The object includes durable materials that are slightly light responsive. Examples; oil and tempera painting, fresco, untied leather and wood, horn, bone, ivory, lacquer, some plastics. 3. Medium sensitivity The object includes fugitive materials that are moderately light responsive. Examples; most textiles, watercolours, pastels, prints and drawings, manuscripts, miniatures, paintings in distemper media, wallpaper, and most natural history objects, including botanical specimens, fur and feathers. 4. High sensitivity The object includes highly light responsive materials. Examples; silk, colorants known to be highly fugitive, graphic art and photographic documents. Table 1. Classification of sensitive cultural property from CIE 157: 2004 8

2. To decide of the maximum of total luminous exposure accepted Sensitivity and classification for cultural property The table below lists materials in four categories according to their sensitivity to light Category Description 1. No sensitivity The object is entirely composed of materials that are insensitive to light. Examples; most metals, stone, most glass, genuine ceramic, enamel, most minerals. 2. Low sensitivity The object includes durable materials that are slightly light responsive. Examples; oil and tempera painting, fresco, untied leather and wood, horn, bone, ivory, lacquer, some plastics. 3. Medium sensitivity The object includes fugitive materials that are moderately light responsive. Examples; most textiles, watercolours, pastels, prints and drawings, manuscripts, miniatures, paintings in distemper media, wallpaper, and most natural history objects, including botanical specimens, fur and feathers. 4. High sensitivity The object includes highly light responsive materials. Examples; silk, colorants known to be highly fugitive, graphic art and photographic documents. Table 1. Classification of sensitive cultural property from CIE 157: 2004 9

2. To decide of the maximum of total luminous exposure accepted Sensitivity and classification for cultural property The table below lists materials in four categories according to their sensitivity to light Category Description 1. No sensitivity The object is entirely composed of materials that are insensitive to light. Examples; most metals, stone, most glass, genuine ceramic, enamel, most minerals. 2. Low sensitivity The object includes durable materials that are slightly light responsive. Examples; oil and tempera painting, fresco, untied leather and wood, horn, bone, ivory, lacquer, some plastics. 3. Medium sensitivity The object includes fugitive materials that are moderately light responsive. Examples; most textiles, watercolours, pastels, prints and drawings, manuscripts, miniatures, paintings in distemper media, wallpaper, and most natural history objects, including botanical specimens, fur and feathers. 4. High sensitivity The object includes highly light responsive materials. Examples; silk, colorants known to be highly fugitive, graphic art and photographic documents. Table 1. Classification of sensitive cultural property from CIE 157: 2004 10

2. To decide of the maximum of total luminous exposure accepted The following table gives the recommended values of maximum total luminous exposure for the different classes of light sensitive objects. MATERIAL CLASSIFICATION BLUE WOOL SCALE TOTAL LUMINOUS EXPOSURE Insensitive 7 & 8 no limit (for conservation) Low sensitivity 7 5 & 6 600 000 luxh/y Medium sensitivity 4 2 & 3 150 000 luxh/y High sensitivity 1 1 15 000 luxh/y Table 2. Total luminous exposure for different classes of light sensitive object interpreted from CIE 157: 2004 11

2. To decide of the maximum of total luminous exposure accepted The following table gives the recommended values of maximum total luminous exposure for the different classes of light sensitive objects. MATERIAL CLASSIFICATION BLUE WOOL SCALE TOTAL LUMINOUS EXPOSURE Insensitive 7 & 8 no limit (for conservation) Low sensitivity 7 5 & 6 600 000 luxh/y Medium sensitivity 4 2 & 3 150 000 luxh/y High sensitivity 1 1 15 000 luxh/y Table 2. Total luminous exposure for different classes of light sensitive object interpreted from CIE 157: 2004 12

2. To decide of the maximum of total luminous exposure accepted 15 000 lx. h/y = 300 hours x 50 lux (1 month) For seven months the dose would be close to 100 Klx h/y (15 000 lx. h x 7 = 105 Klx. h/exhibit) 13

3. Propose different ways to achieve the goals of limiting the illumination • But 50 lux is extremely low illumination, we propose an average of 75 lux with a dynamic lighting between 30 and 150 lux. (150 klx. h) • Illumination of all white surfaces (walls and ceelings) by fluorescents dynamic lighting. • Increase and decrease light levels very slowly to be imperceptible by visitors 14

The relative influence of UV protection for lighting by fluorescent lamps. 15

White wall backlight principle spotlight Fluorescent lamps ceiling White screen wall dress 16

White wall backlight principle spotlight Fluorescent lamps ceiling White screen wall dress 17

White ceiling backlight principle Fluorescent lamps spotlights ceiling Translucent white ceiling wall dress Glossy blavk floor 18

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4. To be able to measure of light exposure • Dosimeters placed at various locations • Sensor for measuring the exposure time 20

Difference in sensitivity of Light. Check according to the illumination source A E of 25 corresponds to a light exposure of 10 000 lux. h A E of 25 corresponds to a light exposure of 18 000 lux. h 21

Dosimeter Lightcheck ( Lido project) E CIELAB : 0 14 19 65 71 22

Dosimeter Lightcheck ( Lido project) E CIELAB : 0 14 19 65 71 23

Determination of the total luminous exposure by looking at the change of color, with the calibration chart 24

Determination of the total luminous exposure on the back of dress #52 18 76 (in showcase # 22 during the time of the exhibit) 19 19 000 lx. h 25

electronic dosimeter The sensor records the light from the start until the lights are off 26

5. colorimetric measurement 27

5. colorimetric measurement « Before » measures of E CIELAB between the object and reference plate « After » measures of E CIELAB between the object and reference plate Determine the difference of color differences before and after exposure 28

Determine the difference of color differences before and after exposure Matière Drap de laine N°inv. 84 -35 -1 idem Tulle Satin à l’envers crêpe velours 52. 18. 66 52. 18. 15 86. 70. 4 52. 18. 43 Location de la mesure E avant E après Couleur de la robe Couleur de la céramique dos marron gris moyen 48 52 + 4 Côté gauche marron gris moyen 49 54 + 5 Bas du ventre (milieu) vert délavé vert mat 28 28, 4 + 0, 4 Sous le nœud épaule droite vert délavé vert mat 30, 6 33, 2 + 2, 6 Haut du sein gauche vert mat 33, 5 35, 2 + 2, 7 Centre droit bas vert mat 31, 8 30, 8 -1 Haut fesse gauche vert mat 31, 7 35, 5 + 3, 8 Bassin face rouge mat 13, 8 13, 6 - 0, 2 Milieu dos rouge mat 12, 7 11, 8 - 0, 9 Fesse (losange foncé) vert mat 47, 3 41, 5 - 5, 8 ¾ dos (losange clair) vert mat 45, 5 38, 2 - 7, 3 Table of results before and after exposure. 29 Ecart

Recommendations - Dynamic lighting, variable in time, variable in illumination, must remain a requirement. Need to review or re-installing a new system of lighting management for showcases on this exhition room. - The exposure time, when the public is absent, must be reduced. It seems unnecessary to open the room two hours before the public comes, when an hour would be more than enough to ensure the proper functionning of electrical and electronic equipment. - Also required the creation of a work lighting for exhibition setting and maintenance other than the light coming from the display cases. 30

Thank you for your attention 31