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[Max] I need help! / CoronaPhysical Mtl & Physical Mtl Questions
« Last post by Jpjapers on Today at 17:21:21 »Recently ive been confused by a few things in the the Corona Physical Material that over the years ive learned to live with. Its possible im completely using the physical material incorrectly and im just used to the simplicity of the corona material.
A few questions;
1. Why does inverting a map in the bitmap node result in a different result than if i invert it within a corona colour correct node?
2. Why do the same PBR maps connected to both a corona physical material and an autodesk physical material render very differently to each other? Ive attached an example compariso_galv.jpg. On the left is a physical material, the right is a corona material. The physical material seems to be almost non-metal in appearance and the corona material appears too much so when compared to the pbr material preview from poliigon (MetalZincGalvanized001_Sphere.png)
3. Why do PBR maps appear different when rendered in corona vs the previews of the material? See the attached material preview from Poliigon ( MetalZincGalvanized001_Sphere.png) and the render from corona comparison_galv.jpg
4. Finally, To get a similar result with metals in the physical material vs the corona physical material it appears that i need to connect the diffuse map to the base weight and base color slot. Why? See attached comparison_nodes.jpg for the result of this.
Ive never really questioned these things before but just learned to live with them.
Is this just a metalness implementation thing that reared its head back when the physical material was released? Much of this doesnt appear to be an issue with non-metals (see plastic comparison) and corona seems to assume that all metals have an IOR of about 4-5 because it lacks the ability to control IOR when in metal mode.
A few questions;
1. Why does inverting a map in the bitmap node result in a different result than if i invert it within a corona colour correct node?
2. Why do the same PBR maps connected to both a corona physical material and an autodesk physical material render very differently to each other? Ive attached an example compariso_galv.jpg. On the left is a physical material, the right is a corona material. The physical material seems to be almost non-metal in appearance and the corona material appears too much so when compared to the pbr material preview from poliigon (MetalZincGalvanized001_Sphere.png)
3. Why do PBR maps appear different when rendered in corona vs the previews of the material? See the attached material preview from Poliigon ( MetalZincGalvanized001_Sphere.png) and the render from corona comparison_galv.jpg
4. Finally, To get a similar result with metals in the physical material vs the corona physical material it appears that i need to connect the diffuse map to the base weight and base color slot. Why? See attached comparison_nodes.jpg for the result of this.
Ive never really questioned these things before but just learned to live with them.
Is this just a metalness implementation thing that reared its head back when the physical material was released? Much of this doesnt appear to be an issue with non-metals (see plastic comparison) and corona seems to assume that all metals have an IOR of about 4-5 because it lacks the ability to control IOR when in metal mode.