There's a great deal of difference. If you were 5ft away the person would be reacting to you, and from 30ft away they would not, so you would get entirely different results. Also, even technically there would be massive differences... the look of the image: 5ft with a short lens will give the field of view and perspective we normally associate with being there... a 200mm lens does not. It looks totally different. It looks like a long lens shot, and removes any sense of presence from the image. I'm sorry, but for a photographer to say there's no difference in 5ft with a 35 and 30ft with a 200 is.. well.. quite surprising.
We've had great long lenses for some time.... they're not a recent invention
Where is this insistence that great street images need to be candid coming from? What a preposterous idea. So if the subject doesn't see you taking the shot its the truth? Really? Care to explain the rationale behind that? Any photographer who knows anything will tell you that there's no such thing as truth in an image alone. You have already edited real life, by choosing the exact moment to press the shutter... what to include, what to exclude. You are merely telling the story YOU want to tell.. not the truth. These candid shots tell me nothing about them. I have no idea who they are, what they're thinking, what kind of people they are. All I have is what you the photographer chooses to give me.
It's just one story... your story... not theirs.
If you are in any doubt about whether the subjects being participants in the shot, or aware of the shot can be more truthful than if they were shot candidly, then take a look at really great work with the homeless... stuff like Margaret Morton (Glass House) or even
Dark Days by Marc Singer. If you do watch Dark Days.. watch the DVD version as there's a "making of" film as well. It demonstrates how Singer got the homeless people to actually be the film crew. They rigged up their own lighting, make their own dollies to run along the tracks... they were empowered totally, yet despite this it's perhaps one of the most honest, real films made of the New York homeless... ever.
You don't need to surprise people or sneak around to get honesty. That's one of the rookie mistakes that unfortunately persists in far too many people.
Documentary and ethnography produce the most honest, realistic accounts of people, and both require full co-operation from the subjects being explored. "street" photography that snipes from across the street is just people putting their own ideas, baggage, prejudices, and wants onto other people without their consent. What exactly is "honest" or "truthful" about sniping people from a distance without knowing anything about them, then representing them however you see fit without their consent? How is that "truthful"?
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BTW.. I'm not saying great images can't be taken without people knowing... just that honesty and truth have f**k all to do with it. You want truth, then get the people being shot to tell YOU what's what.. don't just represent people how you see fit. That's NOT honest... or truthful... that's bulls**t.
