This is a step by step guide to using digital models to predict light levels inside buildings under varying daylight conditions. It defines the state of the art in the Digitl Craft of light simulation.

It comprises a series of pages each devoted to a step in the programme of accurate light simulaiton. The steps in the programme are intended to esnure that there is a high probablility that the light levels predicted by the software are genuinely predictions of what will occur in reality. In these terms there is a goal to produce lioght renders that are real, not merely (in computer graphc terms ) 'realistic'.

Each step is a separate wiki page devoted to the following themes:

1. selecting a software package that has been evaluated by the CIE TC3.33 Evaluation Test Suite
2. agree lighting goals suited to the building's purpose and the goals of the client, the designer and the analyst
3. ensure that the dimensions for the digital model are in real world units
4. obtain measured data on reflectivities
5. obtain measured data on transmissivities
6. construct a lighting model with no light leaks or other such flaws
7. run the render engine with only real tweaks - no time saving approximations
8. return to lighting goals in as guideline for performance asseswsment
9. iterate and compare to / scale against the real world.