At the right end of the status bar are the buttons that control the display and navigation of the viewports.
Some of the buttons change for camera and light viewports. The Field Of View button changes for Perspective viewports.
The state of the navigation-button flyouts for all viewport types is saved in the [Performance] section of the 3dsmax.ini file.
Viewport Navigation Controls
The navigation controls depend on the active viewport. Perspective, orthographic, camera, and light viewports all have specialized controls. The term “orthographic” refers to User viewports as well as viewports like Top, Front, and so on. The Zoom Extents All flyout and Maximize Viewport Toggle, available in all viewports, are included with the Perspective and orthographic viewport controls.
Many of these controls are modal, meaning they stay on for repeated use. The buttons highlights when on. To turn them off, press 
, right-click in a viewport, or choose another tool.
Controls Available in All Viewports
Perspective and Orthographic Viewport Controls
Perspective and Orthographic Viewport Controls
Zoom Extents / Zoom Extents Selected
Field-of-View Button (Perspective) or Zoom Region
Camera Viewport Controls
Light Viewport Controls
