[away3d] Why FOV == 0 in OrthogonalLens

[Von]

Hi all,
It seems OrthogonalLens doesn't has a FOV value,but in Max there is a FOV
value.
How can I get a zoom value from away3d get calculate the FOV value in max,or
calculate a FOV value in max to zoom value in away3d?
I want render both away3d and max to same size image.
Any help will be thankful.