Is there a possibility to point out the blur point in the image with a
mouseclick? Or do you have to do it with the X&Y things?
I have been known to "cheat" using the following method:
Duplicate your layer then clear the duplicate (it should be transparent).
Using the Transform Scale Tool, resize the transparent layer so that
the "circle" handle is situated over the focal point of your blur.
Perform a Merge Down (you now have a layer such that your focal point
is at the center).
Perform your Motion Blur.
Perform a "Layer to Image Size".
The last step assumes that your original layer is the same size as
your image. If this is not the case then it requires a couple of extra
steps to crop your final layer to the correct size.
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