I was at Ellis Island with a 600mm and a tripod, and was told by a ranger to stop taking pictures of the Verrazzano Narrows Bridge. It was 6.7 miles away. He claimed that it was against the law to do so due to Homeland Security concerns. I explained that the bridge was far enough away, and only an element in a landscape, and he said "it doesn't matter." I then pointed out the 100 or so tourists, all of whom were taking pictures of the harbor with their cameras, and asked if he was going to stop them from taking pictures as well. He said no. So I invited him to have a look through my viewfinder, and showed him he had nothing to worry about. His response was WOW! when he saw what I was shooting. I then brought up images on my smartphone that had far greater detail of the bridge, even during construction, that presented more of a problem - especially because they were widely available.

A second time was when I was cycling on the West Side Highway bike path, which passes under the George Washington Bridge - and I stopped to take a picture with my cellphone - the same concerns were expressed by a ranger, but this time I just moved on. It wasn't that important.

Not anywhere near the best places, but those two times were the only times I was asked not to take pictures.