Thanks for this, gave me an entry-point to some further reading/info.
Not sure if I’m going to use this for (single) images, though. All this is based on the aesthetics of a 2 page (or side by side / mirrored) layout. Not using the geometric centre for a single image doesn’t work for me.
I do see the beauty of this method when using 2 images, be it in a single frame or 2 separate frames, especially when using the golden ratio rule (as shown in the Dutch wiki: Gebruik van de gulden snede).