Abstract: In their coeval descriptions Procopius of Caesarea and Paulus Silentiarius emphasise the unique effect of the light and the precious furnishing of the Hagia Sophia after its completion under the emperor Justinian. In order to comprehend the original situation and thereby approach the intentions of the constructors and planning architects, a number of alterations on the building have to be reversed. For this purpose a computer model has been created drawing on the building survey of R. van Nice which reconstructs the architecture in detail and the marble surfaces with their exact coloration. The distribution of direct and indirect illumination by daylight was simulated with the help of the Open Source software package Radiance and made visible using the High Dynamic Range Imaging-method. In this way the pictures reach the capacity and quality of human vision and generate the effect of the reconstructed architecture in an adequate way.
