Museum Lighting - an holistic approach

Among the environmental parameters that effect exhibited artifacts, light is the most complex and the only essential for the observer as to appreciate the artifacts, thus being one of the most critical variables of art exposure. Research on strategies for energy saving and the renovation of light destined to Heritage is examined by daylight admission and Light-Emitting Diode (LED) technology. The extended review of the literature presented below, over museum lighting, evidenced the parallel advance of lighting principles with lighting design, concerning what determines visual quality and perception. Lighting quality is an interdisciplinaryfield of research affecting human activity and under a requested task, visual performance, while at the same time improving well-being. In this sense, the role of the lighting designer is to match and rank human needs with economic and environmental aspects as to architectural principles and to translate the results into a feasible design and an efficient installation. Quality factors for art exposure, involving color fidelity and damage, along with visual perception necessitate of useful metrics through established criteria. The challenge for the museum for a holistic design of natural and artificial light is still missing of substantial metrics, even though recent findings provide some insight on the workflow to establish. Luminance-based design metrics and contrast criteria are used in this study as key strategies for museum lighting, combining comfort and viewing fine arts through advanced computer rendering. The exploration of the transition inside a daylit gallery where moving in the museum environment offers an experience for a series of adaptation changes through photopic, mesopic and dark-adapted scotopic function, along with change on the sensitivity of the spectrum. The luminance appearance and the transition adaptation in the museum field lack of research examination; the relationship of prescriptive requirements and luminance- based design has been explored initially in the field of road lighting, where the relative visual performance has been evidenced to be in the center of the CIE standard for tunnel lighting. Daylight simulation via climate-based modeling, introducing daylight filters as solar shading devices, has been proposed as the object of experimental research, connecting light “filtering” with luminance; this workflow could be applied in several fields of research considering museum environment and give responses in the preservation of artwork involving daylight. The subject of this thesis is the proposal of a ‘trama’ surface installed on windows to reduce and control daylight, studying how energy and conservation targets can be achieved. New light sources and smart control systems will integrate to a holistic approach for museum lighting design.