personality and portrait in studio
What personality of people you try to capture while shoot them in your studio, or you do not think about it at all.
I think that studio portrait is specific and can deal only with desired and real personality.
Personality is inner soul visible in outside expressive appearance of his face, and additionally visible physical surrounding things that go with a person. Examples are: one is always: sad, happy, energetic, lazy, vibrant, smiling, helpful, like bright and silky cloth, how one earn a living, what one carry around in pockets. Character is inner soul not visible through outer appearance. One have to know the person in order to discover his character, e.g. how he handle a problem, how passionate he is about all he does, his behavior toward family or friends, his likes and dislikes, he is dirty or clean person, well organized or not.
People change personality and character (in further text named as personality only) to adapt to current condition, but in all of that changes there is one average personality people are judged by (this do not include artificial personality). Skill needed to get the best out of a reluctant person is more interpersonal and psychological than photographic.
Photographer has to find in his subject a constant point of his personality and character, point that never change.
Personality can be grouped as desired (or mask) personality that people would like to have. An example is masks one can fit over his face which are opportunity to experience a different personality while keeping real personality safely hidden.
Depends on the day. The person. The music. The intended receiver of the photo (e.g., the client -- is this a portrait for the sitter? for their company? for the newspaper? for yourself?).