It might be detectable and definable by spherical co-ordinates, but I wasn't sure how a circular lens was going to
rotate rays passing through it (about its own axis)?
It needs to do this in order to perform the necessary counter-rotation if the camera (and image sensor) plus lens barrel rotates during the exposure.
e.g. if you rotate a simple telescope or magnifying glass, the image doesn't rotate - or am I missing something?
A daft after-thought;
I guess lens axis rotational blur I am talking about mainly occurs because people have a habit of 'stabbing' the shutter button, which moves in an axis that encourages camera and lens rotation and particularly with a DSLR, where their other hand is likely to be around the lens barrel. It occurs to me that if the shutter button actuated directly toward the centre of the lens axis, the movement imparted by 'stabbing' the shutter button would be mostly x-y resolvable and better correctable by in-lens stabilisation.
I did say it was a daft thought
