I started to weight paint the arm of my character (blender 2.8) and noticed that the deform bone rotation of the arm vs the rigify metarig bone rotation is different.
Are they supposed to be off like this?
what can be done to correct this?
Do I need to do something when setting up the metarig prior to generating the armature?
This is what it’s meant to do, yes. I think it’s to more accurately simulate how skin bends around a skeleton.
The only time I have seen this is when I have accidentally moved moved the metarig bones in pose mode before I generated the rig. PS. You could go to pose mode and clear all transforms to check.
Basically what yogyog said, this is a rigging technique used in rigs to deal with things like forearm twisting when you move you forearm from pronation to supination
