German law is quite emphatic about this, if in public I can photograph whatever I wish, although I would be cautious photographing the police, but have done so in the past. In a structured environment I am very comfortable photographing strangers, these are images of an anti-war protest in Munich 5 years ago:
The key to these photographs was that this was a public event with many photojournalists attending, the trick was to blend in with the group and simply take photo's. Not sure I would get away with this in the UK or US.
Considering the risks of photographing riot police in the middle of what could have been an extremely violent protest, I find it strange that I am almost frightened of taking photographs of random strangers. I think much of it comes down to the fact that I do not want to offend someone, the threat of a violent response is not uppermost in my mind.
In any case I have chosen a very safe subject and environment in which to shoot. Opposite Munich's largest park is a large road intersection offering good sight lines and room to move around. Across this junction come many cyclists on their way into the park and perhaps a cold beer or two. I decided to try and capture a few different styles of cyclists as they buzzed past or stopped to wait for the lights. I have used a 70-200mm f/4 zoom lens for this exercise, lighter than my other image stablized f/2.8 70-200. This lens is part of my travel kit, light and yet offering excellent quality. The absence of IS is not an issue when shooting moving subjects as I need a high shutter speed in any case. On some of the following shots I have also added a 1.4x extender for a little extra reach.
First off we have the middle aged flip flop man:
Shortly followed by the banker, clearly looking in need of liquid refreshment
Looking cool the tattoo man waits for the light and then is joined by a pair of sensible cyclists
moving to a slightly different vantage point I came across a younger flipflop man, on a mission not to touch the ground before getting to the beer garden
Across the street a lady in black, not realizing that the street temperature had hit 30 degrees by now waited at the lights
Followed by someone who will shortly be run over by a car she cannot hear yet
Across the bridge come a couple of ladies sensibly dressed for the heat
and a man who is not! But then again his is making up for it in intensity
Down below me someone takes the shaded path along the river bank
and finally someone with some sense gets off and pushes
well down that hill anything else is madness.
That was fun! Whilst taking the pictures I was still fairly ill at ease and was the target of a number of quite hard stares as people went on by wondering what I was doing. There is an unfortunate history in Germany of state surveillance leading to arrest and potentially terrifying consequences. I think people are not happy being photographed, however, they also are not inclined to challenge. This sequence of photographs also did not place me very close to the subjects and I was taking pictures of people as they sped by, I did not enter their environment.