Why do so few characters use JCMs
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Character morphs are quite limited by the weight map if JCMs are not used.
It can take me well over 20 sculpt revisions to get a character morph right. But the 40 or so JCMs take less than 5 hours to sculpt and setup. Seems like a small time premium considering the benefits.
Comments
I find it quite impressive if you can fully sculpt and rig 40 JCMs in 5 hours. Not saying I don't believe it, just that I'm impressed. When I am working on clothing, it can take me days to get all the JCMs right for just one article of clothing.
The JCM sculpts are reasonably very similar for characters, I guess you get an eye for it.
Or more precisely, the problem rotations are very similar for characters (Chest, Shoulder, Collar, Thigh, Shin, Forearm, Pelvis)