Roughness maps

[racoonart]

I must admit that I have not followed the whole pbr discussions over the last couple of months, so I might not know what I'm talking about but wouldn't it be easier to just insert an output map (like my ggx conversion) instead of destructively alter maps in PS via a Lut ?

[Juraj]

All we need is for the current IOR model to become part of 'legacy' check-box. That would be seamless integration of correct behaviour without affecting anyone's workflow or destructing past materials (since the IOR behaves likes this from early Ashikmins' model as well).

That's not PBR. That's just how the specularity should behave. It's bug, issue.

[lacilaci]

I've made a LUT that you can apply to any glossiness map that is using IOR 1.5. This will simulate the proper IOR dimming behavior that Coronas GGX is missing.
If your material is using Roughness, remember to invert it before you apply the LUT in Photoshop.
Load the IOR map with gamma 1.0.

impressive, what does the LUT actually do??

[racoonart]

impressive, what does the LUT actually do??

[lacilaci]

the moment I saw your picture I realized that I could've just loaded the lut in the live curves in photoshop to see that... Sometimes I'm just so slow thinking :D... thank you :)

[Avan]

Guys, i am really impressed depth of your knowledge. Thank you very much. With the last IOR lut fix material is looking perfectly.

[dubcat]

I must admit that I have not followed the whole pbr discussions over the last couple of months, so I might not know what I'm talking about but wouldn't it be easier to just insert an output map (like my ggx conversion) instead of destructively alter maps in PS via a Lut ?

I was actually going to send you a PM when I got back online.
Would be awesome if you could add a little "IOR Fix" button or something to the Converter.

I sampled every glossiness value from 1-0.
Here's the range and values.

Glossiness 1.00 - 0.26 should be mapped to 187 RGB aka IOR 1.50
Glossiness 0.25 - 0.14 should be mapped to 194 RGB aka IOR 1.42
Glossiness 0.13 - 0.00 should be mapped to 205 RGB aka IOR 1.33

When the image is loaded as gamma 1.0 the RGB is 212, 217, 225

This output should connect to the same map as the GGX Output and not after the GGX Output.

I'm using the LUT non destructively with the "VRayLut map", but not everyone has vray installed.
"Convert to log space before applying LUT" need to be disabled in the map.

[Ondra]

Let's hope that Ondra and his team will bring us glossiness fix as promised soon and will make your workaround redundant :]
Excellent stuff nonetheless!

we have it done. But we will probably wait for 1.5 so there is enough time to test it

[dubcat]

we have it done.

[Juraj]

Let's hope that Ondra and his team will bring us glossiness fix as promised soon and will make your workaround redundant :]
Excellent stuff nonetheless!

we have it done. But we will probably wait for 1.5 so there is enough time to test it

Can't we get a Daily of 1.4 that has it feature ? Just 1.4 + this.

[Ondra]

It's a pandora box, because meaning of the most crucial numbers will change. So I will not release it until 1.4 stable is out

[Juraj]

Ah, I just wrote it stupidly then. I did meant after 1.4 is out.

[Ondra]

yep, it will be probably one of the first updates after 1.4

[guest_guest]

Magic


Load the IOR Fix Map with Gamma 1.0

hi dubcat,

is any simpler way to get this? like as an output node with tweaked curve or something like this?

[dubcat]

is any simpler way to get this? like as an output node with tweaked curve or something like this?

This is how you recreate the LUT with an Output map :)