Placement
This video is old and the quality is poor. Louis Smith teaches these techniques at the Realist Academy. If your interested in learning this technique then check out the website for Workshops and courses.
https://www.realistacademy.com/
Louis Smith is a classically trained artist. He studied in Florence, Italy for three years and now resides in his home town of Manchester. His portraits have been exhibited in the BP Portrait Award 2009 and 2011 and Royal Society of Portrait painters 2009-2010.
Place the head off the centre of the canvas, to give space for direction of the face to look into.
You need to fit the composition within the canvas.
Allow for size of head and enough room below the shoulders.
Length of head
6-7in or 15-18cm, around a hand span,
Smaller rather than bigger, gives the impression of looking through the picture plane. Only bigger if going in a large room conference hall etc.
Subject at eye level or higher,
Width of head,
Measure the width compared to the head and place the width off centre of the middle of the canvas
Plumb line
After head is placed,
Draw a vertical line down the face, cutting through the maximum reference points.
Sketchy ghosty lines.
Use a brush with no medium dipped in paint and dried of on a cloth, dark enough to register to the eye.
Use straight lines, they add strength and are architectural.
Brush
Use a 1/3 inch brush, we are not being definite at this stage, looking for broad measurements.
Proportion
Create an armature to base measurements on,
Divide the head into 3 and a ¼ sections. Take If the head is 61/2 inches draw a line ½ an inch under the top of the head and then divide the rest of the head into 3 lines.
You already have lines for the top of the head and chin in placement stage.
1st line = hair line.
2nd line = top of eye brow.
3rd line = line under nose.
Note the line of the bottom lip is half way between the nose and chin.
Now search for proportional differences, within the head. Few people's heads are in proportion so now you can find the differences.
Should look like this
Comparative Measuring.
It just means to compare measurements in relation to each other.
You can now use your dividing lines to measure the rest of the face.
Example
The length between the chin to eyebrow is roughly as wide as the outer eye sockets looking face on.
Use of plumb line,
you can now use the dividing lines to measure outward from the plumb line to determine widths of the face.
Perspective of Face,
Sitter should be on the eye line or above. Remember looking at a picture frame is like looking through a window.
The laws of perspective need to be observed,
Attitude
If the subject is eye level then that is equal.
Looking up is Reverence.
Looking down is beneath you
Rules of perspective all parallel lines converge (even in a face).