As with all binocular fields measured in angles of degrees or radians, these are spherical or circular measures.
Expressing fields of view in linear terms, say metres, is imagining a flat plane or linear measure.
As the binocular field gets wider there is more of a difference.
However, here the fields are modest.
The number N will be modified to correct for these differences.
A radian is an arc equal to the radius of a circle.
That is 360 degrees divided by 2 Pi or 57.295 degrees.
B.
Expressing fields of view in linear terms, say metres, is imagining a flat plane or linear measure.
As the binocular field gets wider there is more of a difference.
However, here the fields are modest.
The number N will be modified to correct for these differences.
A radian is an arc equal to the radius of a circle.
That is 360 degrees divided by 2 Pi or 57.295 degrees.
B.