[Radiance-general] Re: point calcs for verification: oddness

[Rob Guglielmetti]

On Dec 11, 2004, at 1:48 PM, Mark de la Fuente wrote:

> Rob,
>  
> When using IES files, do you think it's better to convert your lamp 
> color to white or use the real color values?  I always use the 
> V-lambda multiplier (something like... rcalc -e 
> '$1=($1*.265+$2*.67+$3*.065)*179' ) and include the color when using 
> ies2rad.  Seems like things get complicated when you are running 
> calculations and renderings and you have different types of sources.  
> Maybe white is best?

Hi Mark,

I use white for lamp color, since the renderings tend to look funky 
when you use actual lamp colors.  RwR goes into this a bit, explaining 
it better than I could, but the general deal is that the eye is still 
better than any machine at dealing with visualizing scenes.  The eye 
does an amazing color-balance job, on the fly, that computer displays 
cannot, so color temperature differences tend to get exaggerated in 
renderings when you use explicit lamp colors.

On the other hand, I botched a point calc that didn't even involve 
cosine evaluation, so you may wanna think 2x (or 10.76x) before asking 
me *anything* about this stuff.  ;-)

Still embarrassed,
Rob Guglielmetti

www.rumblestrip.org