Three dimensional computer reconstruction provides us with a means of visualising past environments, allowing us a glimpse of the past that might otherwise be difficult to appreciate. Many of the images generated for this purpose are photorealistic, but no attempt has been made to ensure they are physically and perceptually valid. We are attempting to rectify these inadequacies through the use of accurate lighting simulation. By determining the appropriate spectral data of the original light sources and using them to illuminate a scene, the viewer can perceive a site and its artefacts in close approximation to the original environment. The richly decorated and well-preserved frescoes of the House of the Vettii in Pompeii have been chosen as a subject for the implementation of this study. This paper describes how, by using photographic records, modelling packages and luminaire values from a spectroradiometer, a three dimensional model can be created and then rendered in a lighting visualisation system to provide us with images that go beyond photorealistic, accurately simulating light behaviour and allowing us a physically and perceptually valid view of the reconstructed site. A method for capturing real flame and incorporating it in a virtual scene is also discussed, with the intention of recreating the movement of a flame in an animated scene.