Activate a Camera viewport. > Viewport navigation controls > Roll Camera
Rolling a camera
Roll Camera rotates the camera about the horizontal plane. Drag the mouse horizontally to roll a Target camera or to rotate a Free camera about its local Z axis.
Note: This button replaces the Zoom Extents button when a Camera viewport is active.
Procedure
To roll a camera:
Activate a Camera viewport.
Click Roll Camera.
The button turns green when it is on.
Drag horizontally to roll the view.
Press ESC or right-click to turn off the button.