Irregular sculpting alpha brush - custom brush

i’m not sure if this is the correct place to post this question, please let me know if not…

So, i’m trying to create some wrinkles in multires and get a alpha map by baking displacement. (blender 2.79)

i’m sculpting with anchored stroke method but independing of image resolution i baked, i have problem in the sculpt shape.

Someone know how can i solve this problem

I don’t have much experience with sculpting but some random thoughts:

1- Did you try ‘Autosmooth’ parameter?
2- Your Alpha might be 8bit image, try 16 or 32 bit maybe

yes, I tried autosmooth and 16bit and got the same result, just did not try 32