Perception of Light in Museum Environments: Comparison between Real-Life and Virtual Visual Experiences

Alternative environments to real-life have been in recent demand in regard to lighting design and in museums. In this study, the effectiveness of the perception of the museum space in simulations or virtual-based environments is studied. Answers to a questionnaire regarding lighting in four different visual experiences are compared: Real-life, virtual-video-based, virtual-photo-based and virtual-render-based. A total of 117 participants were divided into four visual experience groups. Each group answered the same lighting related questions for four exhibition halls in the Natural History Museum of the University of Pisa (Italy), which is housed in the Monumental Charterhouse of Calci. The answers were analyzed using ANOVA and a T-test. The results show that virtual experiences can be acceptable alternatives to real-life experience as the answers were indifferent in more than half of the criteria, and no criterion was affected significantly by experience, regardless of the hall’s characteristics. However, it was found that the hall’s characteristics also had an impact on the perception of the criteria in different experiences. Controlled artificial lighting or uniformly distributed lighting (full day or artificial light) were found to be more indifferent to the experience

Application of climate-based daylight simulation to assess lighting conditions of space and artworks in historical buildings: the case study of cetacean gallery of the Monumental Charterhouse of Calci

Exhibits are often displayed in spaces originally not designed to be museums. Thus, is common for those spaces to fail adequate lighting display conditions, both in terms of the artworks’ conservation and visitors’ comfort. In order to objectively assess if an exhibition meets the required standards it is necessary to establish a proper evaluation method. This work proposes a novel procedure relying on climate-based data and dynamic daylight metrics. The procedure, that considers both artworks’ and visitors’ needs, can provide museum curators with scientific, repeatable data. These data can help them screen out potential interventions until the most adequate is found. The main advantages of the new approach are that, if properly validated, the simulations can substitute annual measurement campaigns (thus leading to time and costs savings), and the results are very reliable (thanks to the use of climatic data specific for the site in exam) and that the effectiveness of potential interventions can be predicted simulating as many sceneries as needed. The novel procedure can be applied to assess the exhibits’ display conditions in historic building whenever daylight is the main light source. The validity of the procedure is demonstrated through its application on a case study: the Cetacean Gallery of the Monumental Charterhouse of Calci, near Pisa. The outcome of the assessment demonstrated that the Gallery is over-lit and the exhibits are being damaged, for this reason four potential interventions have been analysed and compared. The accuracy of the simulations was validated through a comparison with on-site measurements

Assessing museums’ daylighting adequacy without annual measurement campaign: Dataset of a confrontation between measured and simulated illuminance values inside the Cetacean Gallery of the Charterhouse of Calci

Lighting Cultural Heritage is a complex task: light is necessary for the act of seeing, it can even enhance the visual experience [1,2], in addition proper lighting can significantly cut down energy consumptions [3], but on the same time it has detrimental effects on exhibits, especially daylight. In order to safeguard the exhibits from damages, national and international standards provide specific recommendations for exhibits’ exposure, based on their photosensitivity category. These recommendations are the annual luminous exposure(LO) and the Maximum Illuminance Level (Emax), museums’ curators have to verify that the display lighting conditions comply with the standards. Historical buildings are often converted into museums but, as their original purpose was different, the lighting conditions are often inadequate (e.g. too much uncontrolled daylight), therefore the lighting conditions’ adequacy of the space should be assessed [4]. As the name suggest the annual luminous exposure requires an annual monitoring campaign, unfortunately it often happens that exhibits have been exposed incorrectly for prolonged periods, and therefore it is very important to evaluate the need of a fast intervention. In this casuistry a prolonged measurement campaign is not acceptable. Simulations can help running a great number of analysis while reducing the length and expenses of a measurements campaign, however their previsions must be validated. This paper provides the data acquired through measurements and simulations inside the Cetacean Gallery of the Monumental Charterhouse of Calci, near Pisa (Tuscany Region, Italy). The data comprehends horizontal and vertical illuminance measurements, recorded on December the 6th, and simulations run in Grasshopper with the plugins Honeybee+ and Ladybug. The data are related to the research article entitled “Application of climate-based daylight simulation to assess lighting conditions of space and artworks in historical buildings: the case study of Cetacean Gallery of the Monumental Charterhouse of Calci”, published on the Journal of Cultural Heritage [5]

Dataset of virtual and real-life visual experiences inside a museum: survey on visual perception with objective and subjective measures

Occupants’ perception of a space depends on their experience [1–3]. Four kinds of visiting experiences were carried out inside the Natural History Museum of the University of Pisa [4]. The museum is housed, together with the National Museum of the Charterhouse [5], inside the Monumental Charterhouse of Calci, near Pisa. Four of the permanent exhibition halls of the Museum were selected for the survey: Historical Gallery, Mammal's Hall, Ungulates’ Gallery and Cetaceans’ Gallery. A total of 117 participants were divided into four groups depending on their visiting experience: real-life, or virtual based respectively on videos, photos or computer-generated photorealistic images (renders). Experiences are compared. The comparison comprehends objective data (measured illuminance levels) and subjective data (questionnaire outcomes on the perception of the space). The illuminance levels were measured using a photoradiometer: datalogger Delta Ohm HD2102.2 equipped with LP 471 PHOT probe. The probe was placed 1.20 m above floor level, and it was set to measure vertical illuminance at 10 seconds intervals. To evaluate participants’ perception of the space questionnaires were used. The presented data refer to the article: “Perception of light in museum environments: comparison between real-life and virtual visual experiences” [1]. This kind of data provides a base to assess if virtual kinds of experience can be implemented in museum environments as an alternative to the real-life experience, and to understand if such an implementation is detrimental or not in terms of participants’ perception of the space. Virtual experiences can be particularly useful for spreading culture, making it accessible even in presence of moving restrictions for people, such as those in force today due to the SARS-CoV-2 emergency