Some people will be very busy and hardly notice you, others are taking a break and enjoy a moment of peaceful rest. Spot them, and don't miss placing them in context when taking the shot. Respect their privacy: make eye contact, get a silent approval to take the picture, and if in doubt walk up to them and ask for permission. You will be rarely disappointed.
It always amazes me how simple street scenes take on that special character when shot in black and white. For one part it might be that this treatment helps reducing the picture to its very essence. But I am also convinced that some of it comes from our 'visual education' through classical photojournalism.
Anyhow, take advantage of these photo opportunities that are free and ready for you to grab. I for one love the creative boost that comes with them.
Gear notes: D700, 28-200G, 24-70/2.8
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