Use Of Mirror Device w/Large Format As Evans&Levitt
I've heard an interview with Levitt, and she describes using an angle-finder on her Leica, which attaches to the eyepiece, rather than a mirror-tube on the lens (which obviously wouldn't be terribly useful on a rangefinder camera).
You can be fairly inconspicuous with anything that has a waist-level finder these days, most people not being familiar with it.
Use Of Mirror Device w/Large Format As Evans&Levitt
Right angle finders for the Leica were the early WINKO (image reversed right to left) and later WINTU (unreversed image). These were standard Leitz catalog items. The camera was pointed at the subject in a normal manner, while the photographer appeared to be looking off at 90 degrees to the subject's right. It could be used in horizontal layout only. They were made in both black and chrome finishes.
Use Of Mirror Device w/Large Format As Evans&Levitt
Paul's long followup answer above seems to confirm what I said earlier: if the photograph depicts people going about their daily business and is not used in a defamatory or commercial way, there should be no problem. On the other hand, if you think you might use the image in a borderline context, well then, sure, get a model release.
In 20 years of street shooting in public places I've never gotten a model release and I'm not going to start now (there's lots more on street shooting in the Leica forum: http://hv.greenspun.com/bboard/q-and-a.tcl?topic=Leica%20Photography).
If that means my next post will come from the penitentiary, well, I guess I'll just take my chances.
Happy shooting, everybody!
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