Bluing / browning steel

[Kram1032]

-> nk http://en.wikipedia.org/wiki/Refractive ... absorption

I think, tinman knew, what the four values mean... though he didn't show up for EVER...

also his own (quite promising) renderer is gone....

^^

[KilamMalik]

Now tried it with the explanations in that link. It says, the first line of the NK is as follows:

Number 1: 1=eV, 2=um, 3=1/cm, 4=nm. Indigo only supports 1=eV.

Number 2: Lowest eV.

Number 3: Highest eV.

Number 4: Number of lines below that line.

The NK file that I downloaded had the first column as wavelength from 0.1 to 1000 nm. I deleted that first column. Now used that calculator to get the eV from nm:

http://tokes.to.funpic.de/uni/nm-eV-Converter.php

So 0.1 = 12398 eV and 1000 is 1.2398 eV. The NK file had 400 data lines. My first line therefore should be:

1 12398 1.2398 400

But then the eV is backwards from 12398 to 1.2398. Don't know if that is good for indigo, so I reverse the data with Excel. So i have 1.2398 to 12398.

I tried that with fe2o3 (which should be rust), but it looked like silver

I have checked some Indigo NK files and they all had smaller values for the minimum and maximum eV. Maybe that 12398 is too much.

Also, I'm not sure about the stepping. The NK that I downloaded had the wavelength in the first column, but I had to delete this. So how could Indigo know the stepping between the lines? I guess, there is a rule for that, if I knew that, I could maybe convert it better.