Then next step would be to create the difference between both of them. You would get a specular map, also you would probably see the pores, since they reflect differently. It's explained in the "digital Emmely" link earlier in this thread. It is crucial that the model does not move between the shots and both shots use the same angle.

A ship in port is safe; but that is not what ships are built for.
Sail out to sea and do new things.
-"Amazing Grace" Hopper

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