[Radiance-general] specifying sources

[william reynolds]

hi there
i'm after a bit more advice about light sources than i can find in th 
edocumentation, and i was wondering if anyone had any suggestions...

firstly, i want to specify the brightness of my light sources 
accurately. i am using photos (hdr images assembled from several photos) 
to specify the output distribution of the source (theatre spotlights) 
and i know the "light output in lux" at various distances from the lens 
(from here: 
http://www.seleconlight.com/english/support/english/acclaim%20pc.pdf  ) 
and i assume that they give the figure for the centre of the beam, 
rather than the average over the whole field.
what i'm stuck on is what figures i should use for the (rgb) brightness 
in the rad file description of the "light" material.

i need the light output of these sources to be physically accurate, 
because i want to compare them to models using ies-data described 
distributions.
i would like to be able to colour correct these sources (i believe the 
ies2rad will do this automatically) given the colour temperature of the 
bulb.


secondly i want to colour my lights, as though they had colour filters 
in front of the lense, and i dont really understand the colour space 
that radiance uses. can anyone point me towards any resources on this?
i want to model the colours of commercially available filters (such as 
this one:  http://www.leefilters.com/LPFD.asp?PageID=248  ) but i cant 
find any RGB transmission data for them. is it possible to convert the 
XYZ values given on the data sheet to RGB?


thanks for your help again
will