Confussion how to use IOR in maya, and metalness

[Anonymous]

Hello, how are you? to see if someone can clarify some concepts that I have quite mixed and unfortunately I am creating many doubts, 1 .- I'm seeing in several tutorials that the metalness option is used to create specific metals, such as gold, chrome, silver etc, but the question that comes up is xq the IOR option is blocked when creating these metals ?? Whenever I want to create a metal, be it iron, steel, aluminum, I have to use the metalness option ?? and then the IOR ?? 2.- IOR theme I have reviewed several tutorials, and frankly I am bundled, some say that we do not follow the IOR lists that we find on the web, other ones on the refractive index page recommend you use those values, and I have also read that the IOR if we indicate it very high for example 30 does not have an actual effect and it is not recommended, ..... are the tables reliable? The refractive index page that is very complete is a reliable option? then to calculate the IOR of a metal and to be able to recreate it in Maya 2018 what guidelines should I follow to understand it? 3.- I tried to create the typical metal of an iron beam and I did not approach the minimum in any case, could someone help me? to understand this with an example or tutorial or book? I am very clumsy .. thank you and I feel the discomfort

[lee_griggs]

Just use Metalness for metals. There is an iron example here.

[Anonymous]

ok but then, the ior is only for dielectrics ?? I understood that metalness was a plus for videogames, so it is not necessary to calculate the base reflectivity in refractive index?

[maxtarpini]

when using the metallic workflow your IOR is implemented with colors (base and spec color), ie colors get turned internally into a complex IOR.

eventually if you know what you're doing there's an aiComplexIOR shader that you can use to build your own stuff. give it a look anyway as you can switch from 'artistic' IOR to numerical(NK) IOR from within the same shader and see you have the same output.

[maxtarpini]

btw if you don't like the 'metallic workflow' or gives you headaches trying to understand it .. you ain't forced to use it at all ... simply increase the specular (simple) IOR to very high values like 12 etc.

[Anonymous]

Hola Lee,y hola Max, muchas gracias por la contribución, pero todavía estoy confundido, para crear metales, ¿siempre deberías usar Metalness? ¿Cómo puedo ver lo que se puede hacer sin usarlo, entonces no es todo lo necesario? ... y ¿qué es elevar los valores de IOR, al subirlos, no tienen efectos reales? ¿No dejaría de comportarse físicamente real? ¿Y qué hay de la base de la reflectividad?

el punto es que los metales no tienen difusión y, sin embargo, aplicamos un color a su base ... agregando un valor de 1 en la metalidad, empiezo a frustrarme, porque trato de hacer el oro sin usar los ajustes preestablecidos o el Hierro y no consigo nada igual.

there's something that escapes me apart from stupidity ... thanks

[maxtarpini]

I think Lee can speak spanish ! 🙂 I don't and not even willing to 🙂

[Anonymous]

Hello Lee, and hello Max, thank you very much for the contribution, but I'm still confused, to create metals, should you always use Metalness? How can I see what can be done without using it, then it is not all that is necessary? ... and what is to raise the values of IOR, when uploading them, they have no real effects? Would not it stop behaving physically real? And what about the basis of reflectivity? the point is that the metals do not have diffusion and, nevertheless, we apply a color to their base ... adding a value of 1 in the metality, I start to get frustrated, because I try to make the gold without using the pre-established settings or the Iron and I do not get anything like it. there's something that escapes me apart from stupidity ... thanks and sorry for mistake jejeje

[lee_griggs]

Here is an iron example from the user guide using Metalness.

Here is a gold example from the user guide using Metalness.

[Anonymous]

... also make sure to have a nice hdri when lighting metals or reflective materials!

[Anonymous]

hello guys, kyan, in theory the hdri is not of poor quality, in theory, is downloaded from a free hdri website .... I understand that they are reliable. Lee, thanks for the examples of iron and gold, the confusion that I have, is that I understood that the metals were not diffuse and of course I am seeing that we are adding a color in the diffuse and part activates the metalness option whenever we want to create a metal, already playing with the roughness we get different results, however if the weight of the base color and the weight of the Specular add more than 1 it would not stop being the material physically correct? By the way Max I tried the aicomplexior and it helped me a lot, thanks for the inconvenience guys!

[lee_griggs]

>however if the weight of the base color and the weight of the Specular add more than 1 it would not stop being the material physically correct?

No, it is still physically correct.

>thanks for the inconvenience guys!

Anytime, thats what we're here for! 😉

[Anonymous]

What I was talking of was not the quality of the HDRi.. what I meant was that you should use something that is reflecting on the surface of the metal. Metal materials dont have diffuse, all they have is spec.. if you are lighting your object with a boring studio HDRi, you reflection will be boring = your material won‘t look interesting and „unreal“.

when you set your metalness slider to 1, the fresnel will automatically be correct and you adjust the specular roughness till you get the metal you want to create.

[lee_griggs]

Yes, here for example.

[Anonymous]

good night guys! thank you very much for the contribution Lee, it is clear to me! Any hdri free?? Hehehe,excuse me,thanks for helping, I am afraid that I will continue to annoy you in the future, hehehe. kyan, sorry, I did not understand you, and frankly, I think you're quite right in what you say because I think that I miss that little detail, I'll take a look when I have a gap! Thank you,