In this tutorial we specifically address materials that are exhibiting two radically different features, such as paint and metal in this case.
This requires a slightly more complicated setup using an Arion Blend material, because paint and metal have very different Fresnel IOR values, which unless separated into different materials, will render wrong.
Let's take a look at the Substance output and the Arion Render output if we use the Basic method.
|Substance output||Arion Render output using Basic method|
So what happens here is that by using only on Arion BSDF, we are constrained to choose only one IoR, which in this case is the paint's IoR that was left by default at 1.51.
We could decide to use a metal-like IOR for the whole material, but then the paint would look metallic as well and overall that wouldn't look very good.
What we need to do is to use an Arion Blend and copy the same material twice in two different channels of the Arion Blend, then mask the paint material to reveal the metal one.
So, make a copy of the Arion BSDF as you would have created it in the Basic method, and name it 'Metal'.
For the Metal material, you can get completely rid of the Coatings. Disable them and remove the textures from its channels.
Then plug both the Paint material and the Metal material respectively in channels where the Metal is below the Paint one, such as like this:
|Arion BSDF Paint material||Arion BSDF Metal material||Arion Blend material|
The mask texture used in the Arion Blend material #3 mask is the Substance texture 'Mettalic.png', inverted in the Arion Filtex parameters.
And now we get the expected result.
Since Substance roughness range doesn't match perfectly Arion Render's roughness range, you may want to do some tweaking in the Filetex options.
In the next render, the Paint material Coatings Roughness texture's Brightness and Contrast were lowered to -50% each.