customize the thin film color ramp from .xls charts

[plyject]

hello,

I´ve to do some renderings with crystals and they have a special metallic angle dependent coating.
they sent me some .xls charts with all the RGB values in 5 degree steps for transmission and reflection taken from the real life object

is there a way to read this values from the .xls chart to set the thin film to my special needs or is the color ramp pre defined and u can just play with the given values (film index and film with)

thanks for any help,

steph

[DinoMuhic]

Is the color table using 3 channels or 1 channel?
I don't have a definite answer to this but I wonder if the thin film is'nt just a glorified specular color ramp depending of viewing angle.
If this would be the case then you could port a falloff node into a gradient node and port that into the transmission and specular channels. And in the gradient node you would then define the colors, knowing that one far end of the gradient is 90° viewing angle and the other 0°

[DinoMuhic]

However if you want to automate it, I bet someone smart could write an OSL shader for exactly that.

[plyject]

they are 3 channels (RGB)
I´ll try that

thanks for your advice!