I know I had this same issue in poser 7 years ago on an older system but can't remember how I resolved it.
I just installed Poser 8 & so far it's completely useless & frustrating.Every time I load it up,as soon as I touch camera move XZ or XY controls the camera zooms wildly to the right & out from the scene.If I restore the camera it resets fine but as soon as I touch the controls again POW ZOOM to the moon Alice.I've tried different mice & pointing devices to no avail & my system has the necessary stats.
I can't find info on this issue anywhere.I'm about to say screw it & install P7...or something else entirely.