Virtual reality as an experimental tool for mean room surface exitance

An experimental study was developed to use immersive virtual environments from high dynamic range images presented in a virtual reality (VR) headset to facilitate applying the mean room surface exitance (MRSE) metric for research and educational purposes. This study has the potential to overcome significant barriers to conducting experiments in real environments by enabling control, replication and rapid switching of visual stimuli while providing a high degree of immersion. It aims to test and establish the methodological instruments used in the empirical studies to answer the research question: Is VR technology valid for MRSE assessments? Thus, virtual environments were tested against real environments to examine their adequacy regarding the subjects’ assessments of the perceived adequacy of illumination (PAI) and spatial brightness. Outcomes revealed that an immersive virtual environment displayed on a VR headset could adequately convey the visual perception of real space for PAI and spatial brightness. In addition, to facilitate the application of MRSE for students and non-experts in the field of architecture and interior design, a simple software tool to estimate MRSE was validated. The calculation of MRSE was based on a common design software tool, V-Ray for 3ds Max, to record measurements easily, quickly and accurately alongside photorealistic rendering. The results indicate that V-Ray for 3ds Max is a viable tool to assess and visualize the overall perceived illumination corresponding to a level of MRSE.