trans or glass material, rectangular luminous opening problem

radiance-general
1

Hi @all,

1. question:

I have circular plexiglass disc or more a flat cylinder and on top of one side there is a blue LEE Color filter attached. I have the spectrum of the filter and calculated the RGB color values. Shall i make a normal glass cylinder and on top a disc of glass with the RGB values multiplied with the transmittance of the filter? Or would you suggest the trans material ?

2. I have .ies data of a rectangular flood light and convert it into a radiance file. Although the resulting Polygon is glowing, the light output seems to come from the middle of the polygon and not from the whole area. Is this correct?

Thanks and regards,

Christian

2

Hi Christian,

1. question:

I have circular plexiglass disc or more a flat cylinder and on top of one side there is a blue LEE Color filter attached. I have the spectrum of the filter and calculated the RGB color values. Shall i make a normal glass cylinder and on top a disc of glass with the RGB values multiplied with the transmittance of the filter? Or would you suggest the trans material ?

The glass material is probably a better approximation in this case, as it will account for the change in reflection and transmission with angle.

2. I have .ies data of a rectangular flood light and convert it into a radiance file. Although the resulting Polygon is glowing, the light output seems to come from the middle of the polygon and not from the whole area. Is this correct?

That is correct. If you set the -dj option to something between 0.5 and 0.8, you will sample over a larger subregion. (A setting of -dj 1 is allowed, but only works if all the sources in your scene are rectangular.)

-Greg