Early in my career I had, for a number of years, the great honor of assisting Yousuf Karsh, one of the most important portraitist of the 20th Century. I learned much from him but most importanly was that the sitter needs to feel at ease during the process. He would visit with his sitter, getting to know them before ever taking a photograph... all the while observing mannerisms and gestures. During the session he could then recognize when his subject was forcing an expression or gesture and conversely recognize honest moments.
It is important that the final photograph says more about the subject than the photographer.
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