def start_coordsys(self):
        """
        Coordinate system at start of effect.

        All axes are parallel to the original vector evaluation location, with
        the origin moved to this effect's start point.

        :return: coordinate system at start of effect
        :rtype: :class:`CoordSys`
        """
        coordsys = copy(self.location)
        coordsys.origin = self.start_point
        return coordsys