Hi! Thanks for trying it :)
The main idea is: you can't have more FOV (hFov or vFov) than the max value the driver is telling to the renderer. So, no matter the app you use, you are only allowed to see what the headset draws. With the Calibrated version, I've tried to calculate the fixed position that gives you the "max" hFov & vFov possible according to what the headset renders. From there, it can only go smaller or narrower.
To check if any other apps (including mine) are working, remove the facial from the headset and look to the very limits of the cone edge (= the limits of the visible screen). That measure should give you exactly what the headset manufacturer driver states: the max hFov / vFov drawn, not a single second of degree more. Once done that, you can be sure that you are measuring the Fustrum (look it up in Wikipedia) from the right point and the subjective FOV is in concordance with the theory.
:)