Theory of Micro Normal

In order to describe the bumpiness one the surface of an object, there will be a Normal or Grayscale texture in the Bump channel of the Material.

Character face without Normal texture.

Character face with Normal texture.

When having the close-up shot for the object, the Normal effect is insufficient to describe the bumpiness and fine lines on the surface.

By overlapping the tiled Micro Normal texture to the original Normal texture, the body can possess fine lines of the skin.