First off, I'm not blessed with some high-degree of confidence that allows me to walk up to anybody, anytime, anywhere and ask them if I can take their picture. Chances are, neither are you. But it hasn't stopped me from taking some wonderful street portraits, and it shouldn't stop you either.
I'd like to be able to tell you that after you've done this a few times it get's easier. It doesn't. The first time I asked a stranger if I could take their picture, I was shaking and nervous as all get out. Same thing the 10th time. Same thing the 100th time.
What I can tell you is that once you've done this a few times, you'll start to develop a rhythm in how you approach a subject, and at some point, while the nervousness will still be there, you'll be better able to work through it and come away with much better shots.
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