export camera

Hi all:)
I am trying to export camera from blender to 3ds max.
I have got problem which lens value.
In 3ds Max I have got special function to set camera value.

A = 0.036 as float – aperture dimension eg. 35 mm lens
F = .050 as float – Lens value (in mm)
fov = 2atan(A/(2F)) as float

Which data from blender I need?
A is Camera.lens it quite obvious.
what about F?
In blender there is also Camera.sensor_width.
Anyone has got any Idea?
//edit
I found
A=Camera.sensor_width.
F=Camera.lens
:slight_smile: