To view the entire Stage on the screen in Adobe Flash Professional, or to view a particular area of your drawing at high magnification, you can change the magnification level. The maximum magnification depends on the resolution of your monitor and the document size. The minimum value for zooming out on the Stage is 8%; the maximum value for zooming in is 2000%.

If you want to zoom in on an element, select the Zoom tool in the Tools panel and then click the element. To switch the Zoom tool between zooming in or out, use the Enlarge or Reduce modifiers (in the options area of the Tools panel when the Zoom tool is selected) or Alt-click (Windows) or Option-click (Mac OS).

You can zoom in so that a specific area of your drawing fills the window by dragging a rectangular selection on the Stage with the Zoom tool.

To access the Zoom tool, select it in the Tools panel. Here's what you can do with it:

Zoom in or out of the entire Stage by selecting View > Zoom In or View > Zoom Out.
Zoom in or out by a specified percentage by selecting View > Magnification, and then choosing a percentage from the submenu or selecting a percentage from the Zoom control in the upper right of the document window.
To scale the Stage so that it fits completely inside the application window, select View > Magnification > Fit in Window. To show the contents of the current frame, select View > Magnification > Show All, or select Show All from the Zoom control at the upper right of the application window. If the scene is empty, the entire Stage appears.
Double-click the Zoom tool in the Tools panel to reset the magnification to 100%.
Select View > Magnification > Show Frame or select Show Frame from the Zoom control at the upper right of the document window to show the entire Stage.
If you want to see the workspace surrounding the Stage, or to view elements in a scene that are partly or completely outside of the Stage area, select View > Pasteboard. The pasteboard is displayed in light gray. For example, to have a bird fly into a frame, initially position the bird outside the Stage in the pasteboard and then animate it into the Stage area.

To learn more about working with the Zoom tool, see the section titled Using the Stage and the Tools panel in the Flash documentation.