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I was trained in classical animation so I've drawn a lot of hands. It's difficult for me to understand how any AI can produce real hand images. It's not the nu

I was trained in classical animation so I've drawn a lot of hands. It's difficult for me to understand how any AI can produce real hand images. It's not the number of joints, it's not the articulation... it's the relationship of the hand to the skeleton, to the gesture, and to the objects with which the hand interacts. It's great that midjourney can now draw raised hands doing nothing or anime girls holding their hands in a mannerist pose but that doesn't address the real issue. Hands are intentional and laden with tiny muscular efforts that we're primed to perceive. When AI draws a tree we aren't expecting each branch to interact perfectly with a cradled object. It's all arbitrary. I wouldn't be surprised if "AI hand touch-up" becomes a specialist skill for the next five years or so. I don't think the hand issue can be addressed until new models are devised that invest more semantic consideration into a scene.

KineticLensman 4y ago
I pose 3D characters in Daz 3D and completely agree. Getting a rigged hand to hold an object such as a wine glass or mobile phone is virtually impossible to do realistically by guesswork. I usually have to hold a real object myself to understand what is going on. With experience I am learning some common patterns but I find there is no substitute for the 'hold-it-yourself' principle.
- littlestymaar 4y ago
  What's really interesting is that it's something both extremely hard to get right, and also super easy to diagnose as "wrong" when not done properly: you need a lot of training to design convincing hands but anyone can judge you for bad hands.
  - KineticLensman 4y ago
    Yes. This is actually why life drawing of models is such a good exercise. You can draw a tree or a house badly in the sense that it doesn't (say) have the proportions of the original but it can still look okay to someone who hasn't seen the original. But draw a person with their eyes too close to the top of the head and it immediately screams 'wrong'
digitallyfree 4y ago
It would be useful if the AI could identify the figure and impose a predefined 3D framework or skeleton as constraints for drawing. Like if one wanted to generate a human or animal there would be such a rig in place. That skeleton would in turn constrain joint rotation, proportions, and obviously the number of fingers. I can only speak for SD but I've had some success using img2img on a CG or hand drawn figure to get the correct pose. The downside of that is that you have to use a low strength value to ensure that it actually follows your image.
- GaggiX 4y ago
  Have you tried the openpose controlnet model? It seems to work well, but unfortunately does not cover hands.
  - deleted 4y ago
    [deleted]
  - GaggiX 4y ago
    I cannot edit the comment anymore but it seems I was wrong: https://www.reddit.com/r/StableDiffusion/comments/1144vyb/controlnet_openpose_hand/ https://www.reddit.com/r/StableDiffusion/comments/1144vyb/co... in this post they discuss and use the openpose model with also hands covered.
IIAOPSW 4y ago
>we aren't expecting each branch to interact perfectly with a cradled object. We are. Sometimes if its subtle and camouflaged it slips past us. >It's all arbitrary. Its not. You are right there are probably fault modes of AI we don't notice most the time, and fault modes that bother us a lot. But its not arbitrary. We are better at noticing certain things aims more than others because that's what we evolved to see.

KineticLensman 4y ago

I pose 3D characters in Daz 3D and completely agree. Getting a rigged hand to hold an object such as a wine glass or mobile phone is virtually impossible to do realistically by guesswork. I usually have to hold a real object myself to understand what is going on. With experience I am learning some common patterns but I find there is no substitute for the 'hold-it-yourself' principle.

littlestymaar 4y ago
What's really interesting is that it's something both extremely hard to get right, and also super easy to diagnose as "wrong" when not done properly: you need a lot of training to design convincing hands but anyone can judge you for bad hands.
- KineticLensman 4y ago
  Yes. This is actually why life drawing of models is such a good exercise. You can draw a tree or a house badly in the sense that it doesn't (say) have the proportions of the original but it can still look okay to someone who hasn't seen the original. But draw a person with their eyes too close to the top of the head and it immediately screams 'wrong'

digitallyfree 4y ago

It would be useful if the AI could identify the figure and impose a predefined 3D framework or skeleton as constraints for drawing. Like if one wanted to generate a human or animal there would be such a rig in place. That skeleton would in turn constrain joint rotation, proportions, and obviously the number of fingers. I can only speak for SD but I've had some success using img2img on a CG or hand drawn figure to get the correct pose. The downside of that is that you have to use a low strength value to ensure that it actually follows your image.

GaggiX 4y ago
Have you tried the openpose controlnet model? It seems to work well, but unfortunately does not cover hands.
- deleted 4y ago
  [deleted]
- GaggiX 4y ago
  I cannot edit the comment anymore but it seems I was wrong: https://www.reddit.com/r/StableDiffusion/comments/1144vyb/controlnet_openpose_hand/ https://www.reddit.com/r/StableDiffusion/comments/1144vyb/co... in this post they discuss and use the openpose model with also hands covered.

IIAOPSW 4y ago

>we aren't expecting each branch to interact perfectly with a cradled object. We are. Sometimes if its subtle and camouflaged it slips past us. >It's all arbitrary. Its not. You are right there are probably fault modes of AI we don't notice most the time, and fault modes that bother us a lot. But its not arbitrary. We are better at noticing certain things aims more than others because that's what we evolved to see.