This is one of a series of images taken at a recent demonstration/carnival/procession/etc. in East Village, NYC, NY. Canon Elan 7E, 100-400mm IS, Provia 100F, natural light.
Note that the lens used was a huge help. I was able to fill the frame with head-and-shoulders from far enough away so that I did not have to get into people's faces (yeah, yeah, I know, it isn't really street photography unless you do :-)) with my camera. At the same time it being image-stabilized allowed me to easily hand-hold a 400mm lens.
