In this week's lesson for the Back to Basics workshop I demonstrated step-by-step how to create a portrait on toned paper (http://www.strathmoreartist.com/artist-studio/about/). As a supplement to that video I thought it might be a good idea to offer some information about the structure of the human face for anyone who may be interested in this subject but who is approaching it for the first time.
We'll begin with a few general notes: first, all measurements will be based upon the overall height of the head (from the top of the hair -- NOT from the hairline on the forehead -- to the tip of the chin) and overall width (from temple to temple); and, second, this system of measurements is intended as a general "ruler" -- each person is unique in a variety of subtle ways, noting how your subject differs from the "rules" and depicting those differences is how you will achieve an accurate portrait.
First vertical measurement -- beginning with the face looking straight-on at you, imagine a line down through the center of the nose, from top of the hair to tip of the chin. Dividing that line in half will give you the (general) position of the eye line.
Second vertical measurement -- divide the vertical line segment running from the eye line to the tip of the chin in half and you have the position of the base of the nose.
Third vertical measurement -- divide the line segment running from the base of the nose to the chin in half and you have the position of the bottom of the lower lip (not the line between the lips.)
First horizontal measurement -- with the eye line extended from temple to temple, note that the vertical centerline divides the face in half.
Second horizontal measurement -- divide the eye line segment running from the temple to the vertical center line in half. This gives you the position of the pupil of the eye.
Second horizontal measurement -- divide the line segment from the pupil point to the vertical center line will give you the position of the inner corner of the eye.
Third horizontal measurement -- divide the line segment between the pupil point and the temple will provide you with the outer corner of the eye.
NOTE: Each eye is one eye width. The distance between the two eyes is one eye width. The distance between the outer corner of the eye and the temple is half an eye width.
When the subject's face is relaxed (showing no emotion) --
- the inner corner of the eye lines up vertically with the outer edge of the nostril (the "wing" of the nose)
- the inner edge of the iris (the pigmented part of the eye) lines up with the outer corner of the mouth