Before you begin repositioning your shots, make sure you have set the aspect ratio of the output frame.

You adjust the aspect ratio when your source material was shot in a format that differs from the intended delivery format, for example, if you shot in 35mm film (1.33 aspect ratio), but will deliver in a widescreen-format aspect ratio of 1.85. Or, you may have shot in a widescreen format at a 2.35 aspect ratio but intend to output a format for television (1.33 aspect ratio).

For information on adjusting the aspect ratio for a cut, see Setting the Aspect Ratio.