One of the new features in Vectorworks 2011 is the ability to use the camera to create a viewport. If you use this technique, you do not need to create a crop object, and you can edit the camera settings after the viewport is made, if you need to change anything.
Place a camera on the design layer. Remember, the camera becomes part of the viewport (like any crop object).
Use the camera to create a viewport, and place it on a sheet layer.
If the camera view is not the way you want it, you can change it.
Update the viewport to see the finished results of the changes.
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