[Radiance-general] Glazing transparency/reflectivity study

[Galen Burrell]

I'm considering doing a study comparing the transparency (as viewed from outside) of two glazing types on a building modeled in radiance.  The study would render several viewpoints (and view angles looking up the facade) for the multiple glass types under a variety of sky conditions (sunny, cloudy, etc).  The primary goal of the study would be to as follows:

1. Demonstrate how exterior transparency changes with different glass types (with different coatings and exterior reflectances)
2. Demonstrate how exterior transparency changes with angle of incidence
3. Demonstrate how exterior transparency changes based on ratio of interior to exterior illuminance (or more accurately, luminances).

I'm only interested in this as a comparative study: does glass type A look clearer than glass type B when viewed at X angle and under Y sky condition, and Z interior/exterior illuminance ratio.

My question to the list is:
1. Comments on the usefulness of this study?
2. Advantage of using Optics 5 rad file (BRTDfunc) over glass primitive?  My understanding is it more accurately captures the color of the glass and reflectivity... anything else?

Thanks,
Galen
____________________________________________________________
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://radiance-online.org/pipermail/radiance-general/attachments/20090115/0d0404ac/attachment.htm