the skin detailing techinque is something im using for all the digital doubles i work on.
unlike using texyz or surface mimic face displacements, i need the skin structure to be unique for every character in order to get a close match
its not perfect but im getting closer with practice
L_arnold | R_reference
it doesnt require special technology or light arrays if thats what you meant.
its just about the technique. and right now im not ready to disclose the process, sorry for keeping it a secret
the UE4 skin shader is the subsurface profile one. it has limitations but has a really good sss, even tho the backscatter isnt working yet and it has just one spec lobe
the ref breakup comes mostly from displacement (normal map in the last UE4 case) but there are ofc maps used in the reflectance to control the spec inside the occluded parts of the pores and skin folds