Too mee it looks like you have botched the installation of the Better Scopes - perhaps having them switched around.
Appart from that - there is no x1 or x4 zoom in my mod.
The observation scope and the attack scope both had x1,5 and x6 as zoom's. This is reflected in my mod. Further the binocular and the TBT both have x7 in zoom.
The reason that the ships are slightly larger in the observation scope is that the scope image (the hole you look out of) is slightly larger. Thus the angularangle needs to be adjusted acordingly so the ships present them selfs correctly at any given range.
no matter what the ticks in the scope should cover X amount of feet at Y range. This is measured in both degrees (angular field of view) and in feet (linieer field of view). Both scopes have a angular field of view of 8 deg. at high power (x6) and 32 deg. in low power (x1,5)
For example, in hight power with 8 deg. (angular) field of view has a (linear) field of view of 419,4 feet per 1000 yards. Meening a target of 420 ft. in lenght placed at a range of 1000 yards should touch both the left and right side of the periscope view.
As long as the FOV is less than about 10 degrees or so, the following approximation formulas allow one to convert between linear and angular field of view.
Let
A be the angular field of view in degrees. Let
L be the linear field of view in feet per 1000 yards. Let
M be the linear field of view in millimeters per meter. Then:
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