Relux Lighting Calculations
Relux is a private limited company funded by a consortium of lighting manufacturers from across Europe. It has acquired the lighting design software developed by the Swiss Lighting Industry Association, and now provides that software as a service to customers. Software, manuals and a support forum are available on the Relux website:

www.relux.biz
Roblon Fibre Calculator
Roblon Fibre Optics is the lighting division of the Danish company: Roblon A/S. The Roblon Lux Calculator offers a simple and quick way of calculating lux values and selecting light generator, fittings, fibre type, fibre length and numbers of fibres. It is possible to generate an IES-file based on the selected fibre lighting system and using that you can apply the fibre lighting system to a professional light planning software.

www.roblon.com
CIBSE
The Chartered Institute of Building Services Engineers - Lighting Society, is a recognized authority on interpretation of European Lighting standards and practice. They produce the authoritative 'SLL Code for Lighting', and a range of other publications on lighting matters in general.

www.cibse.org