SBP3D zoom out limitation

Why is it that I can only zoom out very little?I have a 3D scene, models and elements that are made to a specific scale (I do not want to scale them down in SBP3D) and from there I would export cameras and layouts to FBX.I can only zoom out very little - only 3 steps - using either the “1” and “2” shortcuts and the space+middle-button combo. Very little zoom-in zoom-out possibilities.Is there any way to increase the zoom-in/zoom-out limitations, or - alternatively, define a different scale factor in SBP3D so that my 3D elements come in smaller?Thanks,Dani.