this is a simple matcap maker,that i was playing around, its just works if its rendered from the material render option, and as you can see there are two setups one its the principled shader that its where i take it out the image done with opengl render to make the another setup from the cedric lepiller matcap tutorial, and if you notice its pretty diferent the normal reflections of both, but i think that looks more realistic the principled one. also the matcaps from blender are previewed like the another setup but are built-in in blender. here i leave the download if you wanna test it, happy blending 
!! https://files.gamebanana.com/bitpit/matcap_maker.blend
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