Fairly commonly I import a model from other programs into Houdini that has already been textured. Typically, there are the usual albedo maps but frequently a specular map, normal map, and displacement map. To reassign these accurately in Mantra shaders, I've done a lot of guesswork for typical settings. I often need to reduce the normal scale to around 0.1 and displacement scale to 0.001. I've assigned specular texture maps to the reflectance texture but also frequently inverted the specular texture in Photoshop and assigned it to the roughness channel as well. For the normal scale, in Mantra, one can pick normal range of 0 to 1 (for 8b) or -1 to 1 for floating. Which is more common from substance painter, zbrush exports, or textures from 3dscanstore or texturingxyz? There is also settings in Mantra to invert the x or y. From which programs will one need to do this? I would like to do this logically rather than just play around with the settings until it looks good. What are your suggestions?

Island
There is also settings in Mantra to invert the x or y. From which programs will one need to do this? I would like to do this logically rather than just play around with the settings until it looks good.

I came across this handy list:
https://www.marcelvanduijn.com/tutorials/programs-normal-map-opengl-or-directx/ [www.marcelvanduijn.com]