Lighting 

Lighting here is overall this portraits best feature, the photographer in this photo uses darks and lights to show off the curves and details in his face that work well with the black and white.

Expression 

This photo shows Robert Downey Jr. looking very concentrated at a object that could be out of frame. The photographer took this photo in such detail sort of showing the viewer a more tough side of Robert.

Background 

The background of this photo is black, I assume the photographer chose this simplistic background to contrast with the lights and darks contouring his face. 

Pose and Posture

The pose and posture of this portrait show a more relaxed side of Robert using exposed close up photography in a relaxed, mid action pose.

Eyes and Direction of Gaze 

Robert is looking away from the camera as if it isn't there, this says that he is trying to portray a more natural side of himself. 

Color and Contrast 

Color isn't a very important part of this at all because it contains no color at all, but contrast is very important here because it creates the contours around his face.

Why I picked this photo

To start I picked this photo because my favorite types of portraits it seems are close high detail photographs in black and white. I think those three components are just a very good combination, I was also drawn towards this because I think it takes real skill to perfect lighting in such a way this photographer portrayed Robert Downey Jr. here.