Resize the image and click to view the initial Golden Sections, and the left arm's arc of abduction centered on their natural cross point, being vertically a bit wider than the right one; this was done for comparison to show some vertical compensation to the shoulder rotation upwards (page 50 click here to view, and the Back arrow to exit
– full image).
The passages through several stages of this search will be proudly represented in the next figure, by clicking on which they alternate in an instructive progression.
The φ plot of the square's half side (1.618 of 2, that delimits the height of the shoulders articulation and the extension) [1st click], as it was plotted since the page 26 at the initial stage of the study, pink colored in the figure, was scaled up to the height of the square, then duplicated in a golden profile [2nd click].
It's interesting to watch better now how the vertex c, i.e. the φ of the man height, that marks the vertical position of the soulders, is scaled (white arrow) to the s position, whose vertical marks the horizontal proportion 2/φ of both heads of humerus over the arms extension, as the cross point highlighted above.
This vertical pinpoint of the body upper golden center was also rotated 90° at the page 27 to show the horizontal mirrored sections of the square, matching the glenohumeral joints, as well as the 4th Golden Circle from the external circumference, as it will better fit from now on.