Just wonder.. if you go tour.. see this guy/lady or old lady and you want to take their portraits..
A. Do you approach them and ask them to post for you?
B. Walk around and grab the best apportunity to capture when they are not aware.. if they look at you, then only you ask for permission..
C. Just capture at whatever angle.. as long as you have an apportunity.
If you are doing "A", what is the chances they will post for you??