[Radiance-general] Luminaire modelling using Radiance

[Christopher Rush]

Germán,

Appendix A and Appendix B of this linked document are excellent reference for the file format of IES and Elumdat files:
http://www.helios32.com/Thinking%20Photometrically%20II.pdf

One of things you’ll see is that the IES file includes a crude dimensional information for the X Y and Z size of the luminaire. Negative numbers in the file can be used to indicate if a dimension indicates a dimension of a round rather than rectangular shape. In manufacturer IES data the geometric information is often missing altogether, Z dimension is omitted for recessed luminaires, or the X and Y dimensions are in the wrong places in relation to the photometric distribution.

If you use the IES2RAD command it will produce a geometric definition of the luminaire based purely on the X Y Z dimension definition in the IES file. So it’s best to correct the dimensions by editing the IES file with a text editor prior to running IES2RAD. Otherwise once you run IES2RAD it’s easier to make a mistake if you scale the fixture geometry and scale the intensity accordingly after the conversion.

-Chris
____________________________________________________________
Electronic mail messages entering and leaving Arup  business
systems are scanned for acceptability of content and viruses
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.radiance-online.org/pipermail/radiance-general/attachments/20150807/c14acb85/attachment.html>