[Radiance-general] Re: direct/indirect photometric

[Greg Ward]

Hi Chas,

You are right -- I had forgotten this feature of lboxcorr (and 
boxcorr).  There is a caveat, though, which is using the -i value of 
0.56419 requires that you be working in meters, and likewise the box 
dimensions must also be specified in meters for the units to work out 
correctly.  In this case, the A1 parameter gets set to 1 by ies2rad and 
the lboxcorr applies the correction.  (Remember that the box must be 
centered at the origin for lboxcorr to work properly.)

-Greg

> From: Charles Ehrlich <ckehrlich@yahoo.com>
>
> Greg and John An,
> �
> Unless the new version of Radiance is significantly different that 
> when I wrote chapter 5, I do not think that you need to change A1 if 
> you follow the method described in the book.� The method was 
> specifically designed to address linear sources.� It is also the 
> method employed in the luminaire editor in Desktop Radiance.
> �
> Is it still true that the "lboxcorr" function automatically corrects 
> for the surface area of the emitter?� If not, then we have a major 
> re-write on our hands for the new edition.
> �
> -Chas
>