Nyra specular is blue..

deohboeh · Jun 2014

Why is Nyra's Specular Map Blue? I mean it has a blue-ish tint. It's not for specular and gloss because blue also has value. I saw similar in witcher maps. Is there some reason for this?

huffer · Jun 2014

You can read about it here.

stevston89 · Jun 2014

The basic gist of it is before PBR you had to account for energy conservation in you maps. Energy conservation basically means no more light is leaving an object than it received. So because is so orange you would put blue in the specular to balance the amount of light exiting. The link above explains it well.

Xoliul · Jun 2014

No it's not because of PBR, it's because of shaders not doing their lighting calculations in Linear space.

Eric Chadwick · Jun 2014

Listen to the wise Xoliul.

This is a good article on the subject, with nice pictures too.
http://filmicgames.com/archives/299

Also see
Gamma Corrected Specularity here on the forums.

stevston89 · Jun 2014

Xoliul wrote: »

No it's not because of PBR, it's because of shaders not doing their lighting calculations in Linear space.

I wasn't saying because of PBR. I was saying *before* PBR. I meant to say that you don't have to do it now with PBR workflows. Energy conservation is now a property of PBR shaders so you don't have to account for that in your maps now. Sorry if I implied otherwise.

EDIT:Or I am mis-understanding you and it's not due to the PBR part, but the switch to linear space that we don't have to do this with our spec maps. Either way my intent was to say that you don;t have to do this with the newer engines. It is going to be an old workflow soon.

Xoliul · Jun 2014

Well you are right in saying that with PBR it's no longer a concern; roughness maps are indeed monochrome only.
However, the Linear-space lighting thing is something that was figured out before PBR became all the rage; the article Eric linked is from 2010. Tells you all you need to know about it.

deohboeh · Jun 2014

Thanks for the help guys! Will be going through all of this!

EarthQuake · Jun 2014

Yeah, as Laurens says it was an issue with renderers working in gamma space, most renderers work in linear space today so you no longer need to use the inverse color to get a white highlight, and in many cases you don't need to use color at all in your specular (certain materials like specific metals or metallic paints do need color specular).

Energy conservation isn't really related in any way.

Isaiah Sherman · Jun 2014

Another fun tidbit, the only things that should have color in their specular maps are materials that conduct electricity.

Eric Chadwick · Jun 2014

I'm currently stuck in an older non-linear engine. So the color workarounds are still valid (if annoying).

JordanN · Jun 2014

Isaiah Sherman wrote: »

Another fun tidbit, the only things that should have color in their specular maps are materials that conduct electricity.

I remember reading something about that.

http://www.manufato.com/?p=902

Very interesting.

Swizzle · Jun 2014

Isaiah Sherman wrote: »

Another fun tidbit, the only things that should have color in their specular maps are materials that conduct electricity.

I imagine you could get away with putting colored specular on iridescent surfaces such as mother of pearl, oil slicks, or metallic-looking bugs.

moose · Jun 2014

*shrug*

blue in spec on certain surfaces just looked good. Used it on dark belts & leather all over Gears. White occasionally, but when putting blue spec on a part of a texture my reasons always boiled down to "that looks the best," and made a surface pop off of another.

didn't care if its correct, scientifically accurate, or whatever. doesn't have to have a reason if the end result is pleasing to the eye

if it looks good, it wins!

Neox · Jun 2014

moose wrote: »

*shrug*

blue in spec on certain surfaces just looked good. Used it on dark belts & leather all over Gears. White occasionally, but when putting blue spec on a part of a texture my reasons always boiled down to "that looks the best," and made a surface pop off of another.

didn't care if its correct, scientifically accurate, or whatever. doesn't have to have a reason if the end result is pleasing to the eye

if it looks good, it wins!

+1 don't throw your artistic vision in the trashbin just because PBR is the new thing

deohboeh · Jun 2014

Just curious has anybody used specular with pbr? Do I have to have correctives to use it?

Isaiah Sherman · Jun 2014

Neox wrote: »

+1 don't throw your artistic vision in the trashbin just because PBR is the new thing

Totally. You may only want to constrain yourself to the laws of PBR if you are attempting to create photo-real art.

However, deviation from reality is part of being an artist!

Nyra specular is blue..

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