The tldr on most laws about telephoto/private property/etc is "reasonable expectation of privacy". For example: If you stand on the sidewalk and take a picture

The tldr on most laws about telephoto/private property/etc is "reasonable expectation of privacy". For example: If you stand on the sidewalk and take a picture of someone sunbathing nude on their front lawn, 10 feet away. Assuming there is no fence, you're perfectly in the right. Flip side someone sunbathing nude in their backyard with 10 foot fences, if you took a picture of them say using a drone... then they can go after you because they had a "reasonable expectation of privacy". Same thing with famous people in their backyard and the paparazzi who get out the 800mm lenses and take pictures from the next mountain over. The famous person could reasonably expect some privacy in their backyard.