Theoretically, long lenses should let you capture faces and license plates very far away.
For example, over 900 feet away from a 1080p camera one should get over 40ppf from a 100mm lens.
But how well does this work in practice?
In this test, we took 3 long lens cameras, including:
We ran tests from 100 to 500 feet away from the cameras, comparing the theoretical PPF to the actual achieved.