Normal maps give weird squared shadows, why? - (unexperienced user)

Hi, I am trying to combine my normal map and height map (from Substance Painter) in Cycles.
At the bottom you can see them (they’re rotated clockwise here, and cropped, just to let you see them).

As shadow, I obtain always this squared blocky area where the smoothing also disappears, and as lights I obtain those weirdness. And I have never understood the why.
So now it’s the right moment. What’s wrong here? (click to enlarge…)

its hard to tell since all your screens are so cropped, but it seems your normal texture node is set to COLOR. it needs to be NON-COLOR.

also, the strength might be a bit high.

Oh thanks, I’ll try… I thought that normal maps were needed to be set as “color” since they have colors… While the height map is set on non-color since it’s in greyscale.
By setting a normal map as “non-color”, am I making it just like a height map? If so, why do we need the normal maps in adding to the height maps?

You need to understand what the color/non-color data switch is about:
A texture set to “color” will be gamma-corrected (“linearized”) in order to be integrated into the linear workflow.
A texture set to “non-color data” will be treated as is without gamma correction. This is important for textures that either already are in linear color space or are in fact data encoded as color, such as normal maps.

Thanks!!! I didn’t knew that…