Simulation and calculation
Architects and lighting designers use different methods to convey ideas and technical details and communicate these to those involved in the planning process. Concepts can be visually compared during the design phase in order for decisions to be made prior to construction. Since the 80s the established methods of sketching, model making, sampling and drawings havebeen extended by techniques of digital simulation.
Evaluation and presentation
From the digital sketch through to realistic surfaces and luminaires
Simulation and image processing
Abstraction and swift realisation through digital image processing
Quantitative and qualitative simulation
Physically correct numerical values and aesthetically impressive images
Simulation and reality
The limitations of simulations close to reality
Modifications in the lighting design process
Modelling, definition of materials, illumination and rendering
The light simulation has proven to be a useful tool in the visualisation and verification of the lighting design. Initially, a number of steps are required for the preliminary planning of the rendering: the concept idea and the sketch, the 3D CAD model and the specification of the light sources and surface properties. For professional light simulations, the designer uses specialised software such as 3ds VIZ/Max or DIALux. Most CAD programs are not able to simulate light with physically accuracy.
Topologies and geometries of models
Simple and complex settings for shading and texture
Virtual luminaires and daylight simulation
Differences between radiosity, photon mapping and ray tracing
Aesthetic appearance, accuracy and calculation speed
The planning and design of lighting installations involves a number of technical and economical calculations. Usually, these relate to the average lighting level or the exact illuminance at individual points in the room. In addition, it may be useful to determine the luminance levels in specific areas of the room, the quality features of the lighting such as shadow effects and contrast rendition or the cost of a lighting installation including maintenance cost.
Planning based on the number of luminaires and illuminance
Inverse square law to calculate the illuminance distribution
Taking the reduction of luminous flux into account
Evaluation of the visual comfort: Unified Glare Rating
Utilisation factor method
Estimated calculation of lighting installations
Investment and operating costs of lighting installations
The lighting design process requires detailed information to ensure compliance with the standards relating to illuminances and visual comfort. Thus for the simulation programs, luminaire manufacturers provide files that contain data on the lighting technology of the luminaires.
These planning examples illustrate why light simulations are useful tools in the planning process. Along with the representation of optimised luminaire arrangement, the visualisations also help communicate the design concept. At the same time, the examples give an account of a historical development - from the first use of virtual luminaires to reflector calculations to the representation of dynamic, coloured lighting concepts.