Author Topic: IOR for unfinished wood?  (Read 8418 times)

2018-08-16, 18:23:02

danio1011

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Hello,

I often have to do raw, unfinished wood exteriors.  I find with an IOR of 1.52, even with a low reflection glossiness and bump, I get a bit of a plastic look.  I remember hearing that unfinished wood is a 'lambertion' and didn't have reflectivity in the same way.  Would it be physically correct to set the IOR to 1.0?  Or is that crazy talk?

Thanks,
Daniel

2018-08-17, 04:29:03
Reply #1

Njen

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An IOR of 1 is technically a vaccum, even air is about 1.000293. No dielectric would be close to an IOR of 1, as most dielectric surfaces are roughly between 1.35 to 1.7, with 1.52 being near the most common value. I really wouldn't go lower than 1.35 for rough wood.

If you are looking for a rougher wood, try adjusting the glossiness and bump of your surface.
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2018-08-17, 13:59:19
Reply #2

matsu

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Make it really rough (like 0.25 or something) and add a bit of bumpmap. That usually works for me, anyway.

2018-08-17, 13:59:43
Reply #3

Nekrobul

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1.52 is perfectly fine for the wood.

But wood itself is very tricky and there is 80% chance that you would be needing to use blend fresnel falloff material trick to make proper wood texture.
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2018-08-17, 19:00:28
Reply #4

danio1011

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Thanks all for the feedback!  1.35 and low ref. glossiness\high bump is working pretty well.  I'd be curious about the blend fresnel falloff trick?  Is this to emulate figure or the 'fuzz' of rough wood (similar to fabric)?