Diane Arbus' portraits seem to always be lit with direct flash or flash a bit off to one side. Arbus doesn't focus on making the subject look good but rather exposing their true self, their eccentric nature. She doesn't make her subjects pose, she just makes them look at the lens. Generally, there are no props to be found in the picture: just the subject and whatever clothing they are wearing. Arbus really focuses on her subject and tends to fill the whole square frame with the person. I personally really enjoy her style; I love the shots she's done of ''alternative lifestyles'' and such. Her images feel real, they show people for who they really are and not what society's norms would like them to be.
Going in an opposite direction, there's Edward Steichen. He has no interest in showing the true nature in people; he is a lot more fascinated by the glamourous side of his subjects. Steichen sees beauty as this still, posed facade people have. Contrarily to Arbus, he asks his subjects to pose in an elegant manner and often with props (as seen above on all three photographs). He often uses side lighting to accentuate faces and his photographs are usually filled with interesting shadows to add a little extra to each photo. I also enjoy Steichen's strong sense of beauty and elegance.
I think both photographers are amazing at what they do and I find it hard to pick a favourite out of the two.
August Sander also takes photographs in a ''true'' manner. He often shoots environmental portraits where like Arbus, doesn't ask his subjects to smile but just stare into the camera. Sander is more interested in what people do and how they feel towards it instead of who they are. Any props used in one of images has to do with whatever the subject does for a living. He seems to use flash but off camera.
Sally Mann's style is a lot more focused on feelings, especially those of children. Looking at her photographs, you can often feel what the subject is feeling. Mann doesn't pose her subjects; she captures them doing whatever they were doing. The props are also related to whatever the subject was doing at the time and they add a feel of realism to each photograph. The lighting is most likely natural or very diffused flash in some cases. Like Arbus, Mann often captures these odd little moments. She also has this strange elegance to her photographs even though they are not posed in the slightest.
