Is "diffuse" baking option supposed to be affected by metallicity and subsurface?

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1

So I discovered this some time ago, baking the diffuse texture isn’t really the same as albedo. Even if you check only “color” under influence, the bake is going to be messed up if you have high metallicity and/or subsurface on the material.

It basically bakes in those attributes as well. Idk if metallicity and subsurface are considered as a part of the lighting influence or not. But intuitively if I’ve only checked color under influence, I expect it to bake just the color (the albedo). So is this expected behavior or a bug?

I am using the latest 2.90.1, also tested in 2.91. Found this bug report here: https://developer.blender.org/T69826
He’s talking about the same issue but I didn’t really understand the response. He said that baking the “base color” isn’t supported. Does he mean the albedo by that? If so then the baking options are a bit misleading in my opinion.

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I think what Brecht means by Base Color is: whatever is fed into the ‘Base Color’ input of the principled shader.

The reason that it isn’t that what is baked, is that the ‘Base Color’ of the pricipled shader is not the same as the ‘Color’/Albedo of the diffuse component. Effectively for rendering the pricipled shader is decomposed into several basic shaders (diffuse, glossy, SSS, anisotropic, emission), each with a ‘Color’ value different from the 'Base Color* value of the principled shader (in the general case), depending on the principled settings,