news
- 16.11.2006
- / realizations
Czech Marionette and Circus Museum in Prachatice
National Museum launched its new exposition called Czech Marionette and Circus Museum in May 2006. The space selected for the placement of the exposition was the original library at Velké náměstí in Prachatice. Exposition is located on three floors. On the first floor, there is entrance hall and cash office. The exposition itself can be found on the second and third floor. The first part of the exposition is dedicated to history of the Czech puppet from the oldest puppeteers through family and group theatres to professional stage settings. Apart from traditional Devils and Punch, visitors can come across puppets made according to the models of M. Alš, V. Sucharda and J. Trnka. It is possible to watch famous stagings of puppet plays in small historical theatres right at the exposition. In the second part – in the only circus museum in the Czech Republic - the visitor can see not only posters, photographs, documents, but also a circus with trapezes, Persian pole, one-wheelers, juggling equipment and circus costumes. As a part of the exposition, there is even a motorcycle that Bears and Cibulka drove.
The exhibitory spaces of Museum of Czech puppet are located in the original spaces of municipal library. Due to a different use of the space, it was necessary to offer a new lay-out of lighting of the exhibitory spaces. One of the requirements of the assignment was the use - at least in part – of original luminaires. For this reason, the basic set and stand-by lighting is realized by original luminaires and the exposition lighting set is realized by new luminaires.
Concept of lighting
The system of lighting in exhibitory spaces consists of three separate lighting sets: The basic lighting set, the exposition lighting set and the stand-by set. The basic lighting set serves for cleaning purposes, for lighting during change of exposition and as lighting during checking of exhibitory spaces. It is operated by switches at the doors of each room. This set is designed for the average illuminance level Em = 100 lx. In the ground floor, the set is furnished with luminaires that light the workplace of the cash office with permanent staying. This workplace is designed for the average illuminance level Em = 300 lx. The total installed input of the set is PiZ =1,8 kW.
The exposition lighting set has two parts: exterior and interior. Exterior exposition set serves for lighting of exhibits from farther locations, for lighting of legends and accompanying texts. The set consists of Metro luminaires for halogen reflector bulbs 75 W / 230 V with angles of half luminance 10° and 30°, placed in three-circuit rail system Standard and independently pendant luminaires Cestello 3x50 W. Metro luminaires are furnished with scattered glass and refractors for shorter distance and for more extensive objects that enable to change the form of the luminance curve. Two of the rail system circuits are connected via input dimmer. That is how a system of jump regulation (100%, 70%, 60%) is created for the luminaires in the rail system.
The second part of the exposition lighting set consists of luminaires placed in show-cases or right in the freely installed theatres. Fluorescent luminaires 36 W and 58 W are used for lighting of larger show-cases and theatres. Light diodes (LED) and optical cables are used for lighting of smaller show-cases. This part of exposition lighting is connected to DALI control system that enables fluent regulation of light flow of light sources ranging from 10 – 100 %. The set of exposition lighting is controlled centrally from the cash office and control room via touch control panel.
Owing to the designed regulation (fluent and jump), the exposition lighting set enables the setting of illuminances on exhibits ranging from 50 – 150 lx. Installed input of the whole set according to a qualified estimate is PiE = 9,0 kW. Regarding the regulation of this set, the real input of this set will be according to a qualified estimate PiEreg ~ 6,0 kW. Original system of stand-by lighting was kept. Only functionless luminaires were repaired and luminaires with pictographs were added.
Protection of exhibits
One of the important principles when lighting exhibitory spaces is the protection of exhibits against harmful effects of radiation of light. Damage of exhibits is influenced by four basic parameters:
- Spectral sensitivity of exhibits
- Amount of incident radiation
- Spectral composition of incident radiation
- Time of exposition
The first parameter cannot be influenced. However, it serves for the classification of the exhibit into a certain category of sensitivity. For this category, micro-climatic conditions in which the exhibit can be exhibited are stated or recommended. These conditions are in practice described by the following values:
a) Value of illuminance E (lx)
b) Content of UV radiation Fe,UV (mW/lm)
c) Time of exposition t (hour)
In addition to the keeping of the set values of illuminance, it is necessary to use light sources that do not contain radiation from the area under 380 nm, or only to a minimum extent up to 10mW/lm (that is the minimum measurable rate with current measuring technology). Three types of light sources with the following parameters are used in the lay-out of exposition lighting:
1. Halogen reflector bulb (HALOPAR, Osram) with dimmed component of UV radiation: Fe,UV=7 mW/lm. Temperature of chromatics of halogen bulbs is Tcn =3000 K and colour rendering index is Ra = 100. An important fact is that when dimming a halogen bulb, the colour tone of the radiated light is changed and therefore the temperature of chromatics is changed as well.
2. Fluorescent luminaires furnished with fluorescent bulbs with reduced content of UV radiation (LUMILUX UVS, Osram) are used for lighting of parts of show-cases and theatres. Content of this UV component is Fe,UV < 1 mW/lm. Temperature of chromatics of these fluorescent bulbs is Tcn = 4000 K and colour rendering index is Ra >90.
3. Modules with light diodes are used for lighting of parts of show-cases. The ratio of UV component in the radiated light is minimized, which is given by the principle of formation of light in these light sources. It is generally stated that the content of UV radiation is e,UV=7 mW/lm. Temperature of chromatics of the used diodes is Tcn = 4700K and index of colour rendering is Ra > 80.
Author and commissioner of the exposition: PhDr. Vlasta Koubská, PhDr. Hanuš Jordán
Architect of exposition: akad. arch. Vlastimil Vagaday, g.l. architekti
Lay-out of lighting: Petr Žák, Etna Ltd.;
Luminaires: iGuzzini, SAAS
Show-cases: František Záhrobský, Revyko
Expositional accessories: Luděk Novotný, LND
Production: Ing.Jiří Gregor
