Hello everyone,
This question isn’t really related to Ladybug/Honeybee, it is a Radiance question. I know there are a lot of daylighting experts here that can to help me out.
We want to simulate a red photochromic glass using Radiance. The UV-VIS spectroscopy analysis was conducted and optical characteristics of the red glass including transmittance and absorbance were recognized. Then, the transmissivity of the glass sample was calculated based on the following formula.
Transmissivity = (sqrt (0.8402528435 + 0.0072522239 * Transmittance ^ 2) - 0.9166530661) / 0.0036261119 / Transmittance)
For example, the Transmittance of red glass is 48 % and the transmissivity is 0.5232.
We can model the red photochromic glass in three different ways in Radiance. I appreciate if you clarify which one is correct.
1-First method
Void glass Red_Transmittance_48
0
0
3 0.5232 0.5232 0.5232
2-Second method
Void glass Red_Transmittance_48
0
0
3 0.5232 0 0
Note: In the second way, we remove the parameters of gtn and btn because of red color of the sample.
3- Third method
Void glass Red_Transmittance_48
0
0
3 0.211 0.086 0.196
Note: Some scholars suggested to add the wavelengths of lights (red, green, blue) in the definition of glass material in Radiance. Because of the color of glass, we consider the wavelengths of lights (red, green, blue) in transmissivity calculations and then in the definition of glass material in Radiance.
Among these three ways, which one is the correct way of modeling photochoromic glass in Radiance?
Your help is highly appreciated in advanced.