Santa Trinita Madonna  Madonna Rucellai  Ognissanti Madonna 
Cimabue, c1260/80  Duccio, 1285  Giotto, c 1310 
heighttowidth ratio=1.726  heighttowidth ratio=1.552  heighttowidth ratio=1.593 
6.67% more than &phi  4.08% less than &phi  1.55% less than &phi 
Giotto's Madonna, with rectangle defined by central figures  Same Madonna, with rectangle defined by throne 
heighttowidth ratio=1.83  heighttowidth ratio=1.78 
10% more than &phi  
Does that line divide the height of the mural into Extreme and Mean Ratio? 
The rear wall (down to the bottoms of the windows) forms a rectangle. Is it Golden? I then drew vertical lines at the division between the outer view and the central window. Does it look as if Leonardo may have been placed these windows in these particular spots for a reason?  
I then also drew vertical lines along the other windows. 
Diego Velázquez 80.25" x 49.25" h/w=1.62944 Thus h/w is only .7% off of φ  
Diagram from Bülent Atalay's Math and the Mona Lisa. In it, the painting appears to be subdivided into a smaller  
My version of this same diagram, using a photo from a book on Velázquez. That photo did not have the same proportions as the painting is supposed to, which makes it impossible to draw the internal golden rectangle and square gnomon. Instead, I drew the horizontal and vertical lines through the eyes, and then measured to see how close the various rectangles were to being Golden, and the supposed squares were to being in fact square.
