Above images from tutorial Lenses and perspective, or distortion on a face for beauty are copyright Steven Eastwood
Inspired by an online conversation I had with photographer Steven Eastwood, I just wanted to record here a few remarks I had made on the nature of the '5-eye line.'
You can really see the 5-eye-line in the beauty shot above that was taken from a distance with a long lens. The sides of the model's head are evident.
In the wide-angle closup shot, the '5-eye line' is almost a '3-eye line,' and the side planes of the model's head are no longer visible.
Yes to lense distortion, but in fact the 5-eye-line is a myth. Leslie G. Farkas has conducted several studies, measuring real people, and published his findings in several articles and books. His results show that in 50% of the average north american caucasian the inter-ocular width is larger than one eye (by an average of 3.5 mm, with a variation of 2 to 11 mm). He also found, and you can easily check this for yourself by looking at fashion magazines, that in the "beautiful" face the eyes are farther apart than one eye width.
Concise article:
Farkas, Lesie G. et al., "Vertical and horizontal proportions of the face in young adult north american causasians: revision of neoclassical canons", Plastic and Reconstructive Surgery, Vol. 75, No. 3 (March 1985), pp. 328-337.
You are right. But this is a rough guideline - sort of like approximating pi as 3
It's part of a larger system that goes something like this:
System of proportions based on cranium, not head.
http://forums.cgsociety.org/showthread.php?f=177&t=730905
In the tradition of Robert Beverly Hale (and to a good extent, Glenn Vilppu) I like to use the head width (not head height) an important measurement also known as the 5-eye line.
Unlike full heads, this unit hits a lot of important bony landmarks.
It is the distance from top of head to just under nose.
Another one takes you to the pit of the neck.
Another one takes you to the bottom of the sternum.
Another one takes you to the points of the ribcage.
Another one takes you to the pelvic points.
It is the width of a head.
It is the length of a sternum.
It is the length of a scapula.
It is the length of a clavicle.
Two of them make a humerus; the lower arm is 80% of this.
Three of them make a femur; the lower leg is 80% of this.
It is a handy little measuring tool that I try to make the basis of all my judgments of figure proportions.
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The goal is not to make everyone conform to this. The goal is to have a reference in mind so that you can recognize and draw deviations from it as you encounter them.