Portrait model recovering sculpt details & rigging for facial expressions

Hi guys i need help with this.
After i did my retopology i noticed (obv) sculpt details are gone but found a way to recover them with multiresolution and reshaping, but i still had to open the mouth and make a cavity for teeth so i can
do a simple face rig for expressions so i scrapped that.

Do i have a flaw in process - Is the right way to model the mouth cavity on retopo and recover sculpt details later (somehow) like i did here?

Also if you notice anything else important that im missing im inexperienced with this stuff, the weights
have some glitches/problems but if anyone wants to review that ill post that too sonner or later :sob:

Also i’d accept critiques if you have it so i can improve, u can even PM me.

Lastly sorry for double posting, my previous forum post was unnecessary so i deleted it but
its still up, after 2dys.

The retopo is probably a little too high poly, I mean it can still definitely work but it will be a little smushy to work with.

To recover your original sculpt details create a vertex group on the retopo that includes all verts that are on the surface of the sculpt, that is it should not include interior mouth or inner ear verts. Then add a shrinkwrap modifier to the retopo and use the vertex group to avoid wrecking the mouth and inner ear. when your happy with it apply the modifier. As always work on a backup copy of your file, this is destructive action.

to recover finer details like pores and wrinkles you should bake a normal map.

You mean you get better (deform) control from less topology?

This is the retopo backup - still has shrinkwrap on - did i do it bad somehow?
I mean it has like hard edges on nose and lips - applying any subdividing mod makes shading smoother and more precise and smoothing the verts makes it smoother but it loses its form or does it, anyway am I making a fundamental mistake that i don’t know?

On baking, i had a problem somewhere in the file the bakes turned out transparent (couln’t figure it out) so i took the meshes to a new file and baked it there. The bake worked, but i can’t use it - the details are actually ugly xD but the bake was fine.

Im thinking for this, i should sculpt it twice,

  1. normal sculpt
  2. retopo and open mouth
  3. sculpt in multires
  4. bake

Question about multires, when i subdivide it and make changes to the form, like cheek crease, cheek bone, grab nose etc. (that changes the silhouette), should i retopo that since the overall
form changed, not the details.