Thanks both of you but I really don’t know what to say because I saw a tutorial(it’s the 7 tutorial from the Boujou (5 in my case) Help menu – Using Focal Length Constraints,that one with the old taxi car – if you know it) and that shoot has a zoom.
So they input 4 focal length values at 4 different frames – Indeed the zoom is not that large as mine is and there is also panning too but Boujou solved it well.
From what I see(if i see well :)) the camera doesn’t move.
Maybe I’m missing something,I don’t know.