Stadiametric rangefinding, or the stadia method is a technique of measuring distances with a telescopic instrument, such as a scope.
This is useful in cases where a Rangefinder is not readily available. Some scopes in Arma3 from various Addons and the main game itself implement this functionality.
The following images are taken from Rangefinders that are implemented correctly. It is important to remember that in Arma, if the unit is standing on a grassy surface, on long distances the unit will sink into the ground to simulate being hidden in the grass due to not rendering grass on such distances. This doesent happen on asphalt. The pictures below take this into account.
Mil Dot Stadiametric Rangefinders
However, not all Scopes that contain methods of rangefinding are implemented correctly.
The following entries are examples of non-functioning rangefinders: