As an aside to this. Cameras. You need to add a camera to the scene in DS in order to edit it. The default camera is just that, a "view" into the workspace. Once you've added a camera it will appear in the scene list, the view drop down and once selected in the scene listing you'll depth of field and focal length edit options. If you then use the rotation/dolly tools in the View tool box the the camera will stay at your settings and you can zoom, scroll, fly around, etc..