Since both images share a pose and similar lighting, it is possible to compare some light on the subtle choices Sargent must have of.
1. the values of skin tones are simplified and organized.
2. Key highlights are reserved for the forehead and nose.
3. Hair values are greatly simplified.
4. mustache is reeled in facing up points.
5. face is slightly thinner.
6. eyebrows and eyes are drawn with. precise angles
7. Throughout, there is a visual theme of the heart or chevron shaped
people who watched Sargent painted a portrait amazed by the process. "Lightness and certainty of his touch was wonderful to see. There was never any painter could indicate a more subtle palate, with more mobility, or with a more lively differentiation. As he painted , mouth bloomed in the face, an integral part of it, and not, as in most of the portraits painted on it, a separate thing. It showed how much could be expressed in painting the shape of the forehead, cheekbones and moving muscles around the eyes and mouth, where the character betrayed itself most readily, and under his hands, a head would be an amazing resemblance long before he had so much as indicated the features themselves. in fact, it seemed to me the mouth and nose just happened with the modeling of the cheeks, and an eye, living light, was placed in the socket so carefully prepared. "
Adapted from" John Sargent
* John Singer Sargent, Complete Paintings, Volume 1: The Early Portraits (Vol 1)