how can I determine the Field of View a street view panorama map is using

Question

I notice the Field of View (FOV) degree per street view zoom level is different between browsers

I believe the documented street view zoom level to FOV is

Answer 1

It is not direct answer to a question, but maybe it helps:

There is undocumented option of google.maps.StreetViewPanorama class named 'mode'. You will be able to force rendering mode, and FOV should be the same for eg. 'html5'

Google Maps API custom Street View quality issue