Hi there,

I'm trying to render the most realistic diamond there can be. To do so I need
realistic IOR value and dispersion value. At first I found them in consts.inc
shipped with POV-Ray, namely IOR value = 2.47 (or sth) and dispersion value =
1.035. Then I got across some scientific page about diamonds. As of 2003, the
most accurate value for diamond's IOR is 2.4175, and dispersion value of 0.044.

So my question is: how does 1.035 from POV-Ray relate to 0.044 from the web?
The 0.044 value is said to be "disspersion strength":

  Index of
  Colour    Refraction  Source Line    Wavelength

  Red       2.407       Solar  B-line   687   nm
  Yellow    2.417       Sodium D-line   589.3 nm
  Violet    2.452       Solar  G-line   431   nm

The difference between the indexes of refraction (2.452 - 2.407) is the
dispersion (0.044). (There is a small rounding error.)

http://www.folds.net/diamond_design/index.html#ed_note_04

I'd appreciate any help.

Best regards,
Opal

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