Thanks Colin, that’s what I would have expected. However, that’s not the behavior I’m getting. The problem is mostly the Z origin in the view. If it’s too far (deep) from the geometry of interest the slightest moment of the mouse causes the whole thing to fly off screen and you have to click the Previous (camera undo) to get back to where you were and try again. Most times the origin seems reasonable, but it is quite variable and I have yet to figure out how SketchUp is choosing it.
This model is not simple, it’s a whole house, and most times I’m zoomed in working on some detail. Sometimes the origin of the orbit will be on the surface I’m working on, other times it will be on the other side of the building, 45’ deep in the view… and other times it seems to be 1,000’ deep and the whole house just flies off the screen with the slightest movement.
I wasn’t sure if there were settings to control this behavior that I’ve missed, or if you can manually set an anchor point.