[Physical Camera] Camera.VerticalToHorizontalFieldofView() works not good

Hi. I use physical camera options in Unity 2020.3.6 ver. I want to get the horizontal field of view of my camera, so I use VerticalToHorizontalFieldOfView Function in Camera class. However this function did not reflect the lens shift value. So, in some cases, calculated field of view is not same as real. Is there any options or functions that could be possible to calculate the field of view with physical camera?

Thank you.