Is there some way in Premiere, or possibly in After Effects, which I'm just learning, to take a still, like a psd of a standing ballet dancer, and make her look like she's twirling around very fast?
Kind of but it wont be 3D
To spin (twirl) as in a ballet spin you could use 3D Perspective Effect on a PSD with transparency. (ie clear cut image)
You wont have a "back-side" to the image.
If you want it to look real, you will need to either shoot a real dancer actually spinning, or use something like Autodesk Maya.
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