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1358 Chapter 16: Material Editor, Materials, and Maps
transmitted light. At 1.0, the IOR of air, the object
behind the transparent object does not distort. At
1.5, the object b ehind distorts greatly, like a glass
marble. At an IOR slightly less than 1.0, the object
reflects along its edges, like a bubble seen from
under water. Default=1.0.
Common IORs (assuming the camera is in air or a
vacuum) are:
Material IOR Value
Vacuum
1.0 (exactly)
Air
1.0003
Water
1.333
Glass
1.5 to 1.7
Diamond
2.419
In the physical world, the IOR results from the
relative speeds of light through the transparent
mater ial and the medium the eye or the camera is
in. Typically this is related to the object’s density,
and the higher the IOR, the denser the object.
You can also use a map to control the IOR. IOR
maps a lways interpolate between 1.0 (the IOR of
air) and the sett ing in the IOR parameter. For
example, if the IOR is set to 3.55 and you use a
black-and-white Noise map to control IOR, the
IORs rendered on the object will be set to values
between 1.0 and 3.55. The object will appear
denser than air. If, on the other hand, your IOR is
set to 0.5, then the same map values will render
between 0.5 and 1.0, as if the camera were under
waterandtheobjectwaslessdensethanthewater.
HerearesomemoreIORvaluesforvarious
mater ials:
Material IOR Value
Carbon Dioxide, Liquid
1.200
Ice
1.309
Acetone
1.360
Ethyl Alcohol
1.360
Material IOR Value
Sugar Solution 30%
1.380
Alcohol
1.329
Flourite
1.434
Quartz, Fused
1.460
Calspar2
1.486
Sugar Solution 80%
1.490
Glass
1.500
Glass, Zinc Crown
1.517
Glass, Crown
1.520
Sodium Chloride
1.530
Sodium Chloride (Salt) 1
1.544
Polystyrene
1.550
Quartz 2
1.553
Emerald
1.570
Glass, Light Flint
1.575
Lapis Lazuli
1.610
Topaz
1.610
Carbon Bisulfide
1.630
Quartz 1
1.644
Sodium Chloride (Salt) 2
1.644
Glass, Heavy Flint
1.650
Methylene Iodide
1.740
Ruby
1.770
Sapphire
1.770
Glass, Heaviest Flint
1.890
Crystal
2.000
Diamond
2.417
Chromium Oxide
2.705
Copper Oxide
2.705
Amorphous S elenium
2.920
Iodine Crystal
3.340