How to create a roughness texture

[DustyShinigami]

Guys, I'm completely stumped to the point of frustration. I can't seem to create a roughness texture for my 3D model. I've been having similar problems with a hardness texture as well. I think I've got that one down as best I can, but I'm not sure if it's right and it's certainly not how the author of a book I'm following has done it. Is a hardness texture even a thing? I've tried searching online for a tutorial and can't find anything.

This is the author's texture file: Dropbox - jim_textures.psd

...and this is mine so far: Dropbox - Textures.psd

If you look at the way the author did his hardness texture, he simply copied all his specular layers, grouped them in the hardness folder and added an exposure effect. This way doesn't work for me and I don't understand why. The values for the effect was the same etc., but no matter what I did, *everything* goes black instead of the shapes. In the end, I had to settle for my own way of doing it, which was taking the layer mask from the dark_parts layer and flipping the black and white around. If you look at mine, the results I've got are pretty close.

A similar thing has been done to author's roughness texture, but that too, doesn't work for me. I can't seem to figure this one out. I've tried messing with the curves/levels and got the shapes grey, but now I need to adjust the parts on the layer mask so they appear darker. Everything I've tried gives me the wrong results and affects the rest of the shapes.

At this stage I'm totally clueless what to do. I'd love to be able to replicate the way the author has done it, but I don't mind if someone has a simple but effective method for doing these textures that I can reuse in future.

Any help would be greatly appreciated.

[JJMack]

I do not do 3D work have you tried adding a bump map to your 3d Object?  Roughness I would think it needs to be 3D element not a 2D flat image texture. I played with a Photoshop 3d tutorial to push up the mountains and delet the water.