So can is it accurate to say that the size of the portion of the texture in the render needs to at least match the render size? This is easier for me to visualize in terms of V1/2 textures which have a distinct front and back. If the face is going to be 500 pixels wide in the render (using the pose above), then the front face part of the map needs to be at least 500 pixels wide, irregradless of what the overall head map size turns out to be? Conversely, if you took the full size map and cropped it to just the face, the resulting size would be the maximum resolution facial render size?

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