The device assumes 2 dimensions have been removed from the argument by assuming mounts are in the same plane, in the x axis and the same "tilt" in the y axis so if they line up in the z. Not to be used on bad receivers etc
It is a good thing First focal plane scopes are not Mobius strips and 2nd focal plane are not Klein bottles or this could turn into 5-Manifold Topology dilemma
