Originally posted by Des Des, I did some more digging re the Mona Lisa and it seems near every discussion on the Golden Ratio mentions the Mona Lisa. Interestingly, the more historic discussions seem to centre on the representation of various sized Golden Ratio rectangles, on the face of the subject. More modern discussions seem to attempt to overlay a spiral.
From this, I propose that the obsession with the spiral, also on photos, must be a more modern thing. Historical discussions never mentions the spiral and, instead, deals more with the proportion of the overall painting, or elements in the painting.
I include some different Mona Lisa overlays for context. All show spirals of some description or other but most of the reproductions crop the actual painting or, worse, crop and crunch the aspect ratio, so none of it makes sense at all.
The one on the left is the most accurate of the lot, following the actual Monal Lisa size proportions but, as can be seen with that, it's all conjecture and none of it aligns with the thinking of any historical documentation related to earlier writings about the supposed links to the Ratio.
All very odd.