Have searched around and watched a number of tutorials but am a little confused about a few texture maps and whether different workflows are simply down to user preference or if there is a “right” and “wrong” way to link nodes.
I think I’ve more or less got my head around the concept of reflectivity/specular (amount of reflection) vs roughness/glossiness (sharpness of reflection) but I’m somewhat confused as to how/why so many workflows seem to ignore spec maps. Surely shiny tiles with dirty grout inbetween them would have different levels of reflectivity over the surface? Or are all non-metals literally that close in spec levels that it’s purely the roughness factor controlling the reflection appearance? I guess that makes life a lot easier, just seems somewhat counter intuitive to say that all non-metals basically reflect the same amount of light.
Similar to the above, some tutorials seem to advocate leaving the Specular slider at 0.5, others seem to adjust it up or down as they see fit with no real rhyme or reason, and others will actually plug in a spec map. If it’s true that non-metals more or less reflect the same amount of light, then why shouldn’t this slider always be set to that value? And secondly, I thought that in a metalness workflow the metal map was telling the shader exactly this - i.e. anything black is non-metal and gets a fixed reflectance value. What is the use of the specular slider then? It seems like two things trying to control the one characteristic (amount of reflection). And as far as I can tell, it’s not as if using one “disengages” the other… So basically just a little confused what I’m supposed to do with this slider.
Bonus question: Does leaving the Metallic slider set to 0.0, with no image input, just mean that it’s computed as pure black i.e. computed as the fixed reflectance value of 4% or whatever it is. Or do I actually have to get the plain black metalness map and plug it in every time?
Thanks very much!