Episode 4, Genius of Photography series. This one about street photography and the emergence of colour film. On the former:

Photography discovered its inherent subject in the street The landscape photographers and the portrait photographers were in some ways more stymied because there was an enormous tradition there that they were trapped in...

And going on to talk about the impact of technology on the art:

The street had always been an alluring place for photographers, but to start with at least, it had proved to be elusive. Pioneer photographers could record the architecture easily enough because it kept still, but the life of the street moved too fast for the long exposure times...

So the first street scenes show artfully staged setups or what look like post-apocalyptic ghost-towns. Gradually the technology caught up. Citizens evolved from blurs to all too solid flesh, but the camera's struggle to keep pace with life on the streets left a rich legacy; a visual language of blurs and grain that is unique to photography

Dance, Brooklyn by William Klein, 1956