In Sequencer mode, you can set up an animation that uses multiple camera views.
While Sequencer mode is active, the State Sets dialog appears as a window beneath the 3ds Max viewports, with a track window that shows the cameras in use, and the range of frames during which they are active.
Important: Unlike regular or Compositor modes, while Sequencer mode is active each state has a visible Record button. To make changes to a state, you need to turn on 
(Record) first. While it is active, this button turns red 
.
(Record) first. While it is active, this button turns red . 
The Minimize/Maximize toggle in the upper-right corner of the Sequencer window lets you temporarily hide or restore the window.