Lighting, as a topic of theoretical, methodological, and practical endeavors crosses multiple fields and disciplines. Although it has been a neglected element in the interpretation of built environments, and consequently of humans’ experience and perception, a renewed interest, especially in the last decade, has made light a key component in heritage discussions. This session focuses on the cross-section between these two broad fields, namely heritage and lighting, in theoretical, methodological and technical applications, such museum designs, heritage sites’ development and archaeological interpretations. The aim of this session is to discuss how illumination affects our perception and appreciation of heritage and plays a major role in our understanding of its past and current spatial, temporal, aesthetic and cultural aspects.

The theme of lighting in archaeology and cultural heritage has several different aspects that are of central interest:

  1. Simulation and reconstruction of lighting conditions of different time periods of heritage sites
    Current research and practices on the state-of-the-art of digital tools and methods to simulate lighting situations of the different time periods of heritage sites through industry-academia collaboration is directly related to how we visualize and represent heritage to the broad public. The advancement of hardware and software, especially in the fields of photorealistic rendering, physical realism and supercomputing, has enabled in the last two decades the digital simulation and analysis of natural and artificial lighting in archaeological and heritage sites. A main challenge in the field of lighting simulation is that computer applications have not been developed to take into account variables that existed in the past, thus experts have to face several challenges that hinder research in the field. For example, the reflectance properties of materials used in building construction are unknown, while lighting fuel properties, i.e. intensity, color, distribution, cannot be simulated using western standards and modern values. Or light sources that were used in the past like gas lamps or torches do not have available photometries in lighting software and experimental lab work for the creation of a dataset with such information are necessary to enable the computational simulation of past environments.
  2. Mapping of current state-of-the-arts contemporary lighting techniques and strategies for heritage
    Another important aspect that influences our understanding of heritage is contemporary lighting techniques and strategies that are used to light heritage sites or objects. Lighting is a key element to the perception of a heritage object, building or exterior site, and sometimes, the only way to understand them and make them accessible to the public (e.g. prehistoric cave engravements, roman epigraphy, etc.). Nowadays, the lighting industry offers a variety of technologies and techniques that can be used in lighting heritage. In the field of lighting design, there are a variety of strategies that can be used in the way lighting is planned that can give very different results, from creating an atmosphere to accentuating architectural elements or from silhouetting spatial features to recreating original polychromy of monuments and sculptures (e.g. the experience carried out with the Ara Pacis (Rome) and some churches in Spain. Methodical studies in the last 50 years have attempted to tackle such issues like consequences of museum lighting and artwork illumination by contributing guidelines and best practices in museum lighting. Further, smart dimming systems can create dynamic and interactive lighting environments that can stimulate interest or guide circulation in a heritage site, and even, promote the social inclusion by allowing disabled people to enjoy heritage.
  3.  Sustainable lighting strategy in cultural heritage and technological innovation
    On the era of climatic challenges, it is important to develop guidance on sustainable lighting strategies in cultural heritage to facilitate and promote the uptake of new energy-efficient lighting solutions in response to climate change as well as it take into account the sociocultural impact. The new, technologically advanced, energy-efficient lighting technologies have been incorporated into cultural heritage for different reasons, such as maximizing energy efficiency and minimizing maintenance. At the same time, there is an increasing concern towards the impact lighting has in its surrounding. Light pollution affects the environment, the human circadian cycle and biodiversity. Use of smart systems, dimming and sensors can control lighting to comply with green building codes. This a[sect aims to discuss novel science and technical knowledge when adopting new lighting technologies, but the same time to balance the three pillars of sustainability (i.e. social, economic and environmental) when it comes to lighting heritage sites.
  4. Evidence-based case studies on social impacts of lighting in cultural heritage
    Last but not least, an important aspect to discuss in this field are the social impacts of lighting in cultural heritage as those aforementioned, and guidelines for decision makers for future heritage lighting use. Lighting has adverse effects not only on the heritage sites/ objects but also on users’ physical and psychological welfare. In this aspect, we aim to analyze existing work on social implications of new lighting solutions on those affected actors, communities and collective memory about heritage after new lighting solutions being incorporated.