How to load a metalness texture?

[joshuaKnauber]

I'm trying to load this set of textures on a simple sphere scene. All textures are working fine apart from the metalness map.

I'm using the drei helper, but the same happens with just the react fiber way:

const textures = useTexture({
    map: "./metal/Metal007_1K_Color.jpg",
    roughnessMap: "./metal/Metal007_1K_Roughness.jpg",
    metalnessMap: "./metal/Metal007_1K_Metalness.jpg",
    normalMap: "./metal/Metal007_1K_NormalGL.jpg",
});

// the scene is wrapped with a drei stage for some simple lighting

<Sphere args={[1, 256, 256]}>
  <meshStandardMaterial
    {...textures}
  />
</Sphere>

The result looks like this:

I'm expecting something more like this which I get when I set the metalness to 1 in addition or instead of loading the texture. The metalness map is mostly white, so this is fairly close:

Does anyone have an idea of what I could be missing here? This seems like a fairly straightforward setup. Thanks!

[mwmwmw]

Tough to say exactly what the issue is. Everything looks right. Check to make sure it's loading?

Another idea. The metalness value and the map will be multiplied. So if metalness is set to 0, the map won't be applied.

https://threejs.org/docs/#api/en/materials/MeshStandardMaterial.metalness

[joshuaKnauber]

Yeah, that last point is it. I have to set the metalness to 1. It's still using the metalness map, it's just very subtle with this material, but more apparent with others.
For my use case I will do something like the following to be able to switch between different materials that don't all have a metalness map

const textures = {
    ...useTexture({
      map: "./metal/Metal007_1K_Color.jpg",
      roughnessMap: "./metal/Metal007_1K_Roughness.jpg",
      metalnessMap: "./metal/Metal007_1K_Metalness.jpg",
      normalMap: "./metal/Metal007_1K_NormalGL.jpg",
    }),
    metalness: 1,
  };

Thank you!