You are probably right x-DANGEr. It would have to keep calculating that, as well as other 3-D info., even though it would be converted to 2D sprites at the zoomed-out level. Otherwise, it might be impossible to have the 3-D Models placed in their correct positions once the player zoomed back in to the close-up view. So zooming out would actually be adding to the workload of your graphics card and CPU by adding in the 2D sprites on top of the regular 3D info.