trans or glass material, rectangular, luminous, opening problem

Hi Greg,

thank you very much for your detailed answer, i think the biggest problem i am confronted with are these different terms.
As i understand:
* transmissivity* is the amount of light that is not absorbed inside an object, varies between 0and 1, not taking in consideration the reflection
*total transmittance *the amount of light, that passes through an object, taking in consideration the index of refraction and is less than the transmissivity
But what is* transmission* ?
As i want to apply the color and transmission of this color filter to the glass i got these values from LEE:
Transmission *Y%: 62.4* ; Absorption: *0.21* ; as well as a Spectrum from which i calculated the xy chromaticity values with the mgfilt command: *cxy 0.2884 0.3034*
They have precalculated XYZ and Yxy values for different sources, but i want to apply my own source at different dim and color temperature levels.
To get my RGB values, i have to calculate the XYZ values and for that i need Y! Can i take 0.624 ?
As i understand it, my resulting RGB components should be the same as your example normalized ones.
Then i would apply them to to get the normal transmission.
Maybe i am dead wrong but thats how i see it.