Hi, i am having problems with zbrush 4’s “Symmetry” it is all off target i tried restarting zbrush but it still didn’t work i tried symmetry on a default sphere and it worked, but when i tried it on MY model the second curser isnt on the other side of the model, its far to the left of it. please help me!
Is the model’s pivot point at its geometric center? You can easily tell by looking at the Tool>Preview window and seeing where the cross hair is displayed. If it’s not centered, you have a couple choices. You can press Tool>Deformation>Unify, which will automatically set the model’s axial center to match its geometric center. This is a permanent change and will affect exporting as well. Another option is to press Transform>S.Pivot which temporarily sets the pivot point to the center of the visible polygons. You can then return the model to its original setting later by using C.Pivot.
That window will also tell you what axes the model is using. X is left to right, Y is up/down and Z is toward/away from the camera. So if your model is rotated differently relative to ZBrush’s coordinates you can see that and know which axis to use.
Thank you very much! but i think i have another problem 
when i import obj. into zbrush from maya and the faces are not double sided and when i rotate it it just shows me the other interior. any suggestions?