Portrait-0014.png
There is no such thing as a perfectly front-facing portrait.
Even the slightest tilt, turn, or roll of the head can push proportions and angles off.
That is the first thing to remind yourself when drawing from portrait photography.
Ask yourself: can anyone hold their head perfectly still while looking straight into the camera?
A truly front-facing portrait?
Almost impossible.
Mindlessly following the Loomis method becomes a problem if you miss this point.
The method is a tool for reading the head, not a rule to force onto the reference.
Portrait-0014-reference.png
Portrait-0014-reference-with-loomis.png
See that ellipse?
Every tilt, turn, or roll of the head reveals the equatorial ellipse of the Loomis sphere. In a perfectly front-facing portrait, that same line may look straight. The moment the head moves, it starts to curve.
cwkLoomis v6.5
Helped by cwkLoomis v6.5.