Jump-eye ranging, a common short-distance ranging method for artillery and snipers, can be seen in many war-themed film and television dramas.

Facing the target, stretch out your right thumb between your eyes, close your left eye, aim at the target with your right eye through one side of your thumb, then observe with your left eye through the same side, remember the object aimed at by your left eye, and estimate the distance between the object and the target, multiplied by ten times, which is the distance of the target.

This method can only be roughly measured.