What does it look like? - Quality Control in Simulations of Lighting Appearance

Students in Schools of Architecture around the world are discovering the joys and perils of software that models the physics of light transmission and reflection in buildings. Radiosity and ray tracing options are being explored by program developers in their search for the correct balance between simulation efficiency and realism. The hyper-realistic images produced almost as a by-product of the simulation of the light intensities have their critics in the architectural realm, however they are in the main extraordinarily seductive. These images are what are encouraging students to undertake the often steep learning curve required to run this light simulation software. The paper reports a simple “doll’ s house” calibration exercise where: • the picture “predictions” of the software were compared with photographs of a similar physical model “building” under sunny and overcast sky conditions. • the colour rendition of the software, given different lamp colour spectra, was compared with photographs of similar test patterns. It also describes a case study of three different architects’ design processes examining through interview with the designers the potential impact of this high end rendering software on their design thinking. The software applied to these in architectural practices’ designs comprises Lightscape 1 , Radiance 2