[Radiance-general] accounting for irradiance due to ultraviolet in rtrace

[Lars O. Grobe]

Hi!

> I'm wondering how to account for the irradiance caused by UV in rtrace.
> I know by default (visible light) this is normally implemented
> irradiance = 0.265*R_illum + 0.67*G_illum +0.065*B_illum

That assumes useage of the three channels for RGB. If you decide to use
another wavelength range, you have two options:

1) Use one of the three channels for that wavelength range - and then,
use the radiance covered by that channel, so no summing up of channels.

2) Set all three channels to the same. E.g. use all three with equal
values for your UV range. That means a "grey" image. Then you can use
any channel to get results. Advantage is that in some few places in the
code, useage of the three channels for RGB is assumed. This might lead
to some wrong weighting if you choose option 1), so 2) seams to be
preferable here.

Besides, laws of physics apply...

Cheers, Lars.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 4438 bytes
Desc: S/MIME Kryptografische Unterschrift
URL: <http://www.radiance-online.org/pipermail/radiance-general/attachments/20111021/a2972a5d/attachment.bin>