Selection of suitable lighting systems for use in museums
Lighting is used in museums so that visitors can see and experience the exhibits properly. However, light can also have a detrimental impact as we know from such everyday examples as sunburn, newspaper on a window that turns yellow within days, or photos and posters whose colours change or fade with time.
This small partner project is dedicated to measuring and analysing different lighting systems. The result is a growing database that makes it possible to compare tested light sources and to assess their colour-rendering qualities and potential risks.
The focus is on LED lighting, which is gaining ground in museums because of its cost and environmental benefits, but has been the subject of controversial debate. Unlike traditional light bulbs, LED lighting does not consist of a continuous spectrum but generally comprises three colours added to create white light. For technical reasons, the proportion of blue light tends to be quite high. Which means that the relative potential of damage from LED lighting is higher than from incandescent or halogen lamps. A further point of discussion is whether the colour-rendering index, (CRI, a quantitative measure of the ability of a light source to faithfully reproduce the colour of an object) remains constant over a longer period of usage.
A range of lighting systems and light sources from LED to halogen are entered in the database, which can be made available to anyone who is interested on request. A further aspect of the project is the monitoring of fading rates and the impact of exposure to visible light and ultraviolet (UV) rays on different dye stuffs and colorants using a micro-fading tester (MFT).